AN: Changed the dialogues to English dub
~~~~~~
Somewhere close by, a sniff can be heard as a redhead boy paused on his climb back up the mountain. He raised his head and took small quick sniffs and gasps.

'I smell blood!' He thought in shock and worry as he started to run to where the scent of blood was coming from.

'Someone must be hurt!' He thought as the scent of blood was getting stronger.

He saw just ahead of him, a faint pulsing blue light and he quickly ran towards the direction. Once he came to the scene, the scent of the blood was too much but the sight in front of him shocked and horrified him. Laying in the snow, was a boy around the same age as he is only a year older and in their hand was a sword with a red hilt and the blade was strangely pulsing a gentle blue light.

"Hey! Are you alright?!" The boy cried out in worry as he kneeled down quickly beside the boy.

A weak groan was his reply and he panicked but he needs to help him or he'll get even more hurt.

With much difficulty, he helped the boy up to his feet and gave him a piggyback while grabbing the sword and struggled to climb down the mountain.

"Hang on! I'll get you some help!" The boy reassured him but didn't get a reply as he carried him down the mountain.

After a bit of struggle, the boy was able to reach the base of the mountain and head to the first house he saw and frantically knocked on the door.

"Mr. Saburo! Mr. Saburo, please someone needs help!" He shouted frantically.

The door opened to reveal a middle aged man.

"What's the commotion about, Tanjiro?" The man, Saburo, asked the boy, Tanjiro.

"Please! This boy needs help! He was injured on my way back up the mountain!" Tanjiro said as Saburo was shocked by the sight of the boy and quickly ushered the two inside.

Saburo had Tanjiro lay the boy down gently on a futon and check if the injuries were infected before going on to treat the boy with Tanjiro's help. While waiting for the boy to wake up, Tanjiro's mind is whirling in worry for the boy. Questions about who he is and where he came from and how he ended up injured on the mountain kept bouncing in his mind.

It was around night time when the boy started to show signs of awakening.

Optimus let out a weak and quiet groan as he felt his whole body aching and hurting.

"Hey, you're awake! I'm so glad. You made me worried there." A voice was heard and Optimus weakly turned to see a young boy with dark hair and burgundy highlights with kind maroon eyes.

"Who... Who are you...?" Optimus weakly groaned but started to cough violently.

The boy panicked and called someone named Saburo and Optimus saw a middle aged man come inside with a cup of something wet.

"Here, you might need something to drink." Saburo said as he handed the cup of water to Optimus who sat up slowly only to stop from holding the tea and he looked at his hands in shock.

"A-Are you okay? You have the scent of panicking." The boy said worriedly as it snapped Optimus out of his shock and turned to the two.

Saburo is looking at him in confusion and the boy is looking at him with concern in his eyes.

"I..." Optimus tried to speak but couldn't come up with anything to say so he just cleared his throat awkwardly.

'What... What in Primus is going on? Why am I a human?' Optimus thought in shock.

"I am... I am alright." Optimus finally said.

Saburo didn't say anything but offered the same cup of warm tea again and this time, Optimus accepted it and looked at the contents curiously before taking a small sip and sigh silently as the warmth from the drink instantly made his whole body warm up.

"What happened to you, kid? Tanjiro found you bleeding out in the snow outside." Saburo said as Optimus put the cup down and looked at Saburo and Tanjiro.

"I was... attacked. I didn't see who or what but... all I can remember is the sensation of my body hurting." Optimus half lied.

"I'm relieved that Tanjiro found you before a demon did." Saburo said as he stirred the stew he was making.

'Demon?' Optimus was confused as he sipped the tea.

Tanjiro happened to look outside and saw that the sun was setting.

"Oh. I should be getting home now." Tanjiro said as he stood up and started for the door but Saburo stopped him from doing so.

"You're not going back up the mountain now." Both Tanjiro and Optimus looked at Saburo in confusion and curiosity.

"It's simply too dangerous." Saburo warned Tanjiro as the redhead smiled reassuringly towards the older man.

"Oh, I'll be fine. I've got a good nose." Tanjiro reassured him but Saburo wasn't taking that as an answer.

"You can stay here for the night. Come on. Get inside." Saburo told him but Tanjiro was reluctant since he had to get back to his family.

"No, I'm..." The redhead wanted to protest.

"Don't argue. Just get in here... Before the demons show up." Saburo said.

Tanjiro relented on that before giving in as he went back to Saburo's hut. That night, Tanjiro and Optimus were both given a meal. Optimus was fairly surprised at how good the food tasted, well, this is the first time he ever ate human food since his consumption is Energon.

"It tastes good." Optimus commented as he continued to eat.

"Hmm? What do you mean?" Tanjiro asked curiously and Optimus winced silently at his slip up.

"What I mean is that I have never tasted something delicious before in my life." He said truthfully and got a smile from the redhead.

"Then enjoy your meal." He said as they continued eating.

They both finished it as Tanjiro clapped his hands together and Optimus copied it. He learned from Miko that doing that is respectful and traditional for japanese.

"Thanks for dinner." Tanjiro said happily as Saburo collected their utensils as Saburo gave Tanjiro a futon to sleep in for the night.

Tanjiro started to settle in his futon as something made Optimus question what Saburo told him as he turned to the older man.

"Mr. Saburo, what did you mean by 'demons'?" He asked curiously as Tanjiro listened.

"Uh, yes. I was gonna ask you about it." Tanjiro said. Saburo looked at the two as he started to get ready for bed.

"There have always been man-eating demons prowling about after dark. That's why it's not safe to go outside at night." Saburo warned them and for some reason, Optimus felt dread settle in his gut.

"Time for bed. You can set off for home at first light." Saburo said as he went off somewhere.

'He sure is a strange fellow...' Optimus thought.

Tanjiro then started to lay down as he looked at Saburo with something in his mind. Optimus lay down on his side and seemed to be fast asleep.

"These demons, they're not able to come inside your house, are they?" He asked with a hint of worry in his voice.

"Yes, they could come in." Saburo simply said.

"But, then, wouldn't they just eat everyone?" Tanjiro said as he gripped the sheets a bit nervously.

Unaware of them, Optimus is still wide awake and was listening to the conversation as he made sure to keep his body lax to give the impression of sleeping.

"The demon slayers protect us by killing as many as they can. They always have. Now go to sleep. It's lights out." Saburo said before he turned the lights off as he went to bed.

Tanjiro lay on his back as he thought about what he was told.

'Old Man Saburo, he's been on his own since he lost his family... He must be lonely...' Tanjiro thought sadly before having an idea.

'I'll bring my brothers and sisters by... "You don't have to be scared. There are no demons. You're safe".' Tanjiro thought with a small smile before it disappeared when something occurred to him. This wasn't the first time someone told him something about demons.

'Although, now that I think of it, my grandma used to say the same thing before she passed away.' He thought before closing his eyes and falling asleep.

Optimus waited until they were all asleep as he stood up quietly. Something was telling him to look outside the door and he followed his instincts. He moved the flap of the door slightly to peek out. The streets were empty and quiet aside from the nocturnal creatures singing their songs to the sleeping residence before he looked up towards the mountain as the feeling of dread that he felt earlier intensified. He doesn't know why but something bad just happened. He hopes that everything is okay tomorrow.

He went back to his futon and lay down and closed his eyes and fell into a light sleep.

The next morning came by quickly and Optimus woke up earlier than normal. He didn't have a watch so he probably guessed that the time was around early 5:30 am. Tanjiro was starting to wake up as he yawned.

"Morning..." The redhead mumbled sleepily and Optimus smiled.

"Good morning, Tanjiro. Did you rest well?" Optimus asked as Saburo woke up next.

"I did. Thanks for asking." He smiled.

The next set of minutes of them eating breakfast before Tanjiro was all set to go back home. Optimus decided to accompany him after getting something to cover his star saber.

"You two be careful now." Saburo told them as Tanjiro waved at him as Optimus nodded.

"Thank you!" Tanjiro and Optimus started to walk up the mountain as Optimus marveled at the sight of the snow.

"Never seen snow before?" Tanjiro asked and Optimus shook his head a little.

"I've seen snow before but it was during an incident that I and a... friend of mine almost got killed." Optimus said.

"Whoa, really?" Tanjiro looked at him in surprise and shock.

Optimus nodded and told him what happened though he had to shape the story for a cover story of his experience with the blizzard and scraplet incident.

Tanjiro didn't know what to think about the experience that his new companion went through. They were half way up the mountain and Optimus couldn't help but feel a foreboding feeling in his core.

'Whenever happiness is destroyed... It's always followed...' Tanjiro thought but stopped when the scent of copper came to his nose.

"Tanjiro?" Optimus noticed he stopped before the same scent of copper came to his nose and made something in him squirm uncontrollably.

Tanjiro gasped as he started to race up the mountain with Optimus following quickly.

"Tanjiro! What is wrong?!" Optimus asked as Tanjiro continued to run up the mountain.

"Blood... The smell of blood." He said fearfully and Optimus felt a cold grip in his core as he and Tanjiro ran up the mountain.

When they reached Tanjiro's home, Optimus' cerulean eyes widened in shock and horror as Tanjiro started to hyperventilate when they stopped. The scene in front of them made them look in fear, horror and shock.

Tanjiro felt tears in his eyes as he saw two bodies by the door. On the ground in front of the door are Nezuko and Rokuta, surrounded by a pool of blood.

"Nezuko!" Tanjiro shouted in fear and worry as he ran to his sister and kneels down beside her.

"What happened?! What's going on here?! What happened to you?!" He asked frantically. Optimus followed him before he glanced inside the house and his eyes shrank to pinpricks by what he was seeing as his breath hitched.

"By the Allspark..." He muttered in shock and horror.

Tanjiro noticed Optimus looking inside his home and he got up shakily and went towards the door but Optimus grabbed his arm to stop him and Tanjiro felt devastated. In his home, blood splattered all over the sleeping area and right inside of it all were his mother and other siblings.

Optimus gritted his teeth as his pupils suddenly went to slits for some reason due to the smell of blood but for a different reason. The smell of blood was so strong that it made his throat itch uncontrollably but the second scent made his skin crawl uncomfortably.

"Mom...?" Tanjiro whimpered as he fell to his knees.

Optimus couldn't help but feel sorry and sympathize with Tanjiro. He's so young to lose his family. He could relate to him. He lost comrades, friends and allies to the war and he felt the same devastation that Tanjiro is feeling.

"Mom... Hanako... Takeo... Shigeru... Nezuko... Rokuta..." Tanjiro cried as tears fell from his eyes.

Optimus checked on Nezuko who was above Rokuta and felt her temperature and felt a pulse. It was weak but faint and it made him hope that one of Tanjiro's family survived.

"Tanjiro, she's still alive! We need to get her to a healer!" Optimus said as Tanjiro looked up and noticed the faint breathing of his sister.

A few moments later, both Tanjiro and Optimus race down the mountain with Tanjiro carrying Nezuko on his back and a red and blue kimono covering the female Kamado.

'Nezuko's the only one who's still warm... If we can get her to a doctor, she might live. How could something like this happen? Maybe a bear... That couldn't find a place to hibernate?' Tanjiro thought frantically but due to the cold wind of winter, he's having a hard time breathing.

'I can't breathe! The air is so icy! My lungs hurt!' Tanjiro thought painfully but he couldn't give up.

'Just keep moving! Move those legs of yours faster! We've still got a long way to go to get to town. Hurry! I won't let you die!' He was unaware that while he's carrying Nezuko on his back, her fingers started to twitch a little. Optimus noticed the small movements while running beside Tanjiro and realized what was happening.

"Tanjiro..." Optimus started but Tanjiro didn't hear him due to his panicked thoughts.

'No matter what it takes, your big brother will save you!' Tanjiro swore.

Nezuko slowly awakens but there is something wrong and Optimus quickly notices the changes. Her eyes are completely white, her hair has orange highlights at the tips and she started to growl.

"Tanjiro!" Optimus cried out.

Nezuko pulls on Tanjiro's shoulders and since they were on the side of a mountain, the sudden pull makes Tanjiro lose his balance and the two go tumbling down a cliff.

'Oh no!' Tanjiro gasped

"Tanjiro!" Optimus shouted in shock.

On instinct, he jumped down quickly and grabbed Tanjiro in his arms and he slid them down the mountain as Tanjiro panted heavily to calm down his breathing.

'Optimus saved me... But the snow is the only reason I fell.' Tanjiro thought in shock as his ears were ringing.

"...iro? ...jiro? Tanjiro!" That made Tanjiro gasp in shock as he realized that Optimus was looking down at him worriedly.

"Are you alright? Are you injured?" Optimus asked worriedly.

"I... I'm fine. Thanks." Tanjiro said before he noticed someone else was missing.

"Nezuko? Where's Nezuko?" He asked as he looked around for his sister.

Optimus scanned the area before finding Nezuko standing barefoot on the snow covered floor with her head hung low. For some reason, inside Optimus something was telling him that the girl was not a human anymore but Tanjiro doesn't seem to notice.

"Nezuko, are you okay? You don't have to walk! Let me carry you to town, all right?" Tanjiro said worriedly as he ran up to her as he looked at her.

Tanjiro noticed that Nezuko kept her head hung low which worried him.

"Nezuko!" He cried out in concern and worry.

"Tanjiro, stay away from her!" Optimus shouted as the male Kamado looked at him to see Optimus looking at Nezuko with a wary expression.

"Tanjiro, just step away from her now!" But the warning came too late as Nezuko raises her head to reveal that she's changed. Her eyes were a pale pink color with slit pupils and her teeth became sharp as she lunged towards Tanjiro who jumped back in shock.

Optimus quickly got between them and Nezuko ended up tackling Optimus to the ground and tried to bite his head off but Optimus gritted his sharp canines as his pupils turned to slits unexpectedly.

Tanjiro watched in shock and fear by what was going on and when Nezuko was about to bite Optimus, he sprang into action and took the hatchet from his belt and was able to put the handle of it between Nezuko's teeth. Growling and snarling, Nezuko was able to turn to Tanjiro as she pinned him down to the snow as he gasped since the air was knocked out of him. It was a struggle as Tanjiro kept the handle of the hatchet between his sister's teeth as he saw what had become of his sister. The sharp canines and the pale pink eyes with cat-like slits for pupils! It was an alarming discovery but Tanjiro knew what it meant. She's a demon now!

'Sh-She's... a demon! This is what Old Man Saburo tried to tell me and Optimus about.' Tanjiro thought as an extra weight was added and he noticed Optimus trying to get Nezuko off him but he noticed that he also had the same sharp canines, his eyes were still the same shade of cerulean blue but with cat-like slit for pupils and they were glowing eerily.

'She's a man-eating demon? And Optimus as well?' Tanjiro thought in shock. No! He can't think that way! If Optimus really was a demon, then he should have attacked him and Old Man Saburo but instead, he was trying to help Tanjiro and prevent Nezuko from hurting him!

'Impossible! Nezuko's a human ever since the day she was born! Except she doesn't have Nezuko's scent anymore. But she isn't the one who killed them.' Tanjiro thought as he remembered how Nezuko was on top of Rokuta.

'She was lying on top of Rokuta like she was protecting him, and her hands and mouth weren't covered in blood, but there was one more... There was another scent!' Tanjiro thought. The scent he smelled in his home must be the one who killed his family!

Suddenly, Nezuko's body grew in size and was pushing Tanjiro towards the ground with renewed strength much to both Optimus and Tanjiro's shock.

"How is she getting bigger?!" Optimus gritted his teeth. Even though somehow, Optimus wasn't able to get Nezuko off her brother. Even with his own strength, it wasn't enough. Is this how humans feel when they're worried or scared for their friends?

'And she's getting stronger, too! While I was sleeping like a baby at Saburo's, you were all brutally murdered!' Tanjiro thought in shame and tears started to well up in his eyes.

'It must've hurt... You suffered, didn't you? I'm sorry I wasn't there to help... I have to at least save Nezuko, though! But she's too strong for me to do anything!' Tanjiro thought. There must be a way to snap her out of this! Anything!

"Don't blame yourself, Tanjiro." Tanjiro looked at Optimus in shock and surprise.

Optimus grunted a little as he kept a firm grip on Nezuko to stop her from hurting him as he looked at him.

"Tanjiro, I know you're blaming yourself for what happened but you must not blame yourself for something you weren't aware of or know what would have happen! You're the only one who can get your sister to snap out of this! Do what you must to get her to snap out of it!" Optimus grunted.

Tanjiro looked at Optimus more. What he said made sense. He wasn't aware or knew this was gonna happen and he's the only one that will hopefully snapped Nezuko out of this. He has to try!

"Nezuko! Hang on, Nezuko! Don't give in! You gotta hang on!" Tanjiro shouted to her as tears started to fall from his eyes.

Somewhere in the distance, someone was running towards where Tanjiro, Nezuko and Optimus are.

"Don't let it take control! You gotta stay strong! Just hang on! Please!" Tanjiro pleaded as tears fell from his eyes as he shut them tightly.

Something wet and salty from the scent fell on his cheek and he looked up to see Nezuko looking down at him with tears in her eyes. Optimus slowly let go as Tanjiro stared at Nezuko in disbelief.

When Nezuko woke up, she couldn't remember anything aside from the feeling of hunger as she felt someone carrying her. What was going on? Did something happen? The sudden feeling of intense hunger overcame her as she pulled at the one carrying her. She heard another voice shouting for someone and she fell to the ground below but got back up quickly and had her head low.

The person in front of her was asking if she was okay? But she couldn't ponder on it as the hunger became too great. She's too hungry! She lunged at the person only for someone to push him away and she pinned whoever it was on the ground before the scent of another of her kind caught her attention before the feeling of wood between her teeth made her growl and snarl as she pinned the one who did that to the ground. The person below him was yelling at her as some added weight was on her back but she ignored it. She has a prey to devour to quench her hunger. She made her body bigger before the person yelling at her was able to get through the haze of hunger in her mind and eyes.

"Don't let it take control! You gotta stay strong! Just hang on! Please!"

Demon? Is that what she is? The scent of salt water caught her attention and she saw that the person under her was crying. Something in her squirmed and wilted at the sight of the tears in the warm maroon eyes filled with worry and sadness. Why was he crying? Did she cause this? Tears started to fall from her eyes as she stared at the person under her. Why...? Why does seeing the person under her cry make her angry at herself? The feeling of intense hunger went away as it was replaced by the feeling of sadness, worry and concern for the person under her.

Optimus sighed softly in relief as he let Nezuko go before someone came out of the treeline. The person, who arrived, jumped towards the air to attack Nezuko who realized his presence and before she could attack, Tanjiro pushed her away and some of his hair was cut off. Blade clashing against another was heard as both Tanjiro and Nezuko were blown back from the sudden shockwave.

Optimus gritted his teeth as the person with the sword stared at him in shock and surprise but kept their emotions in check as they jumped back and Optimus stood protectively in front of both Kamado siblings as Tanjiro held Nezuko close to him.

'What the... Who's that? A sword?' Tanjiro thought in shock and worried.

'Is this a demon hunter that Mister Saburo mentioned?' Optimus thought as he kept his sword at the ready.

"Why are you two protecting it?" The guy suddenly asked as he addressed Tanjiro and Optimus.

"She's my sister! We were taking her to get help!" Tanjiro said as Nezuko starts to growl and tries to get away from Tanjiro but he has a firm grip on her.

"Nezuko!" Tanjiro shushed her but she just growled.

"You call that thing your sister?" The guy asked in an almost bored manner.

The guy launches himself at Tanjiro and Nezuko, ready to strike. Optimus moved to protect the Kamado siblings but the guy moved too fast for him and was sent flying a bit from the two and Tanjiro moved to protect Nezuko, only to realize that she is no longer under him. When he looked up, he saw that the guy, Giyu Tomioka, was holding her in the distance by the scruff of her clothes as she growled and snarled.

"Nezuko!" Tanjiro moved to protect her.

"Don't move!" Tomioka warned him and made Tanjiro halt in his steps as Optimus stood up while holding his gut. That's gonna bruise later on.

"My job is to slay every demon I find, which means I have to decapitate your sister here." He simply explained and Tanjiro became fearful and Optimus stepped up while holding his gut and holding his sword.

"No, wait! She hasn't hurt anyone." Optimus said as Tomioka glanced at him.

"Ah, Optimus is right! Back at my house, there was another scent, I'd never smelled before! That's probably the one who killed my family! Nezuko didn't do it! I don't know why she changed into something like this, but still-!" Tanjiro explained but Tomioka scoffed coldly.

"It's really quite simple. She's turned because her wounds were exposed to demon blood. That's how the man-eating monsters multiply." He explained coldly before pointing his blade at Optimus.

"And your companion has demon blood in his veins yet he smells completely clean of human blood." He said as Tanjiro looked at Optimus who looked confused.

"What do you mean demon blood in my veins?" He asked in confusion.

"It's simple. You're a demon and yet you have complete control of your instincts to feed on the boy and the corpses at his home. Why? Why don't you do it?" Tomioka said as he was both intrigued and confused by this.

Optimus didn't know how since he absolutely had no clue at all but thankfully Tanjiro came to his defense.

"Nezuko and Optimus would never eat humans!" Tanjiro said defensively.

"You must be joking. If I hadn't gotten here when I did, either one of them would have devoured you." Tomioka said in disbelief but Tanjiro didn't believe him.

"You're wrong! She wouldn't hurt me! She knows I'm her big brother! Optimus was helping me! And I won't let her or Optimus hurt anyone! I'll turn her back into a human! I will heal her!" Tanjiro said desperately.

"She can't be healed or your friend. Once you become a demon, no one can ever turn back." Tomioka said angrily but Tanjiro didn't back down.

"There's a way, and I'll find it, no matter what it takes, so please let her live! I'll hunt down the one who slaughtered my family!" Tanjiro cried out but Tomioka just readied his sword to kill Nezuko.

"I promise I'll make everything alright! Please! Just let her go! Please don't do this!" Tanjiro pleaded in despair as the images of the ones of his dead mother and siblings came to his mind and caused him to weep.

'Don't-Don't take anyone else away from me.' He pleaded in his mind

Tanjiro gets on his knees and bows with his head to the ground and pleads.

"I'm begging you... Please... Don't kill my little sister... Please don't do it... I'm begging you..." Tanjiro pleaded as he sobbed on the ground.

Seeing Tanjiro on his knees and begging for his only and remaining sibling to be spared made Optimus remember the one who he used to see as a brother and mentor before he turned his back on him which led to the destruction of their home. He turned to Tomioka who had a conflicted look on his face.

"Please spare Tanjiro's younger sister. Spare her for Tanjiro's sake." Optimus pleaded gently. That did it.

Tomioka growled as he snapped at the two.

"Don't grovel like that and give your enemies the chance to kill you!" He yelled as both Optimus and Tanjiro looked at him in shock and surprise as Tomioka continued yelling at them.

"All you're doing is making yourself vulnerable! If it were even a little bit effective, your family would still be alive right now! How can a weakling like you have any hope of finding a way to heal his sister or hunt down a demon?! Don't be ridiculous! The weak have no rights. They don't get to make choices! All they can do is be relentlessly crushed by the strong! Now, maybe the demons know of a way to cure your sister. Maybe! But don't think for even a moment that any one of them is going to respect your wishes, just like I have no respect for you! That's reality. And why the hell did you throw yourself over her like that? Was that your way of protecting her? Why didn't you swing that hatchet? And why would you ever turn your back back to me? Those mistakes are what led to her capture! I could have easily just skewered the both of you and been done with it! He shouted at him angrily but on the inside, he was feeling guilt, sympathy and sadness for Tanjiro who looked shocked to silence.

'Don't cry. Don't succumb to sorrow. This isn't the time to despair. I know you're devastated right now. Your family massacred. Your sister a demon. I know it hurts. I know you wanna scream. I understand. If only I'd gotten here half a day sooner, maybe then, your family would still be alive. However, there's no way to turn back time, so feel it. Feel the pure rage of being unable to forgive. Let it be what gives you the strength to take action. With that fragile resolve of yours, you can't protect your sister or heal her, and you'll never get revenge for what happened to your family!' He thought as his eyes narrowed into a glare as he readied his sword to kill Nezuko.

"No!" Tanjiro screamed and Tomioka stabbed Nezuko on the chest who screamed and cried out in pain.

"Enough!" Optimus ordered as his cerulean eyes became an almost neon color as his pupils became slits.

"Don't you touch her!" Tanjiro shouted.

Tanjiro throws a rock at Tomioka, who bounces it off his sword as the redhead gets up, grabs his hatchet, and runs through the trees, continuing to throw rocks at Tomioka who deflects them easily. When he gets close enough, Tanjiro runs toward Tomioka to attack him for hurting Nezuko.

"Arghhhh!" Tanjiro cried out.

'You let your emotion drive you to charge at me.' Tomioka observed as his expression was steely.

"You are a fool!" Tomioka shouted before he hit Tanjiro with the end of the hold of his sword and knocked him out instantly.

The action made Nezuko stop struggling and growling and she watched as Tanjiro's body collapsed on the floor. She couldn't understand why the redhead tried to protect her even after she tried to eat him. Tomioka watched Tanjiro collapse before he noticed something and someone else is missing

'Huh? What happened to the hatchet? And where's the other one?' He thought in confusion.

He then heard something above and he looked up and his eyes widened as Optimus came down towards him from above with a battle cry and the hatchet was heading towards him fast. Tomioka dodged the hatchet quickly and noticed that Optimus' eyes were glowing intensely as his pupils were thin slits like a demon's. Tomioka quickly blocked the swing of the blade of the human prime and he gritted his teeth when Optimus pushed against him.

"Why? Why are you helping the kid?" He asked in confusion as Optimus gave him a determined look.

"Those who have lost those they hold dear, will continue fighting for those that remain." Optimus said and he quickly switched positions.

The two engaged in a sword fight as Tomioka tried to focus but thoughts about how Tanjiro tried to fight him circulated in his mind.

'Right before he went behind that tree... He threw the rock, and, at the same time he tossed the hatchet. He was only pretending to attack me so I wouldn't realize he was unarmed. He knew he had no way of beating me. His whole plan was to bring me down after I'd knock him out with the other one. These two...' He thought. Maybe... Just maybe...

Nezuko growls and breaks free from the mismatched haori slayer and kicks him away and runs towards Tanjiro as it causes Tomioka's heart to stop beating for a moment.

'Damn it She'll devour him!' Tomioka panicked and he quickly ducked down and swiped Optimus' feet from under him as the prime fell with a grunt before knocking him out.

He turned to Tanjiro as he readied his sword but what he saw astonished him a lot as Tanjiro's words echoed in his mind.

"Nezuko... Nezuko didn't do it. She'd never eat humans! And neither would Optimus!"

Instead of devouring Tanjiro like any other demons would, Nezuko just kneels in front of the unconscious teen with her arms out as she bared her teeth at Tomioka as she glanced at Optimus to see that he was unconscious as well which angered her even more. She doesn't understand what was happening but when the redhead, no, Big Brother tried to protect her and was knocked unconscious, she became furious. No, livid.

The blue haired one was doing the same thing as Big Brother did but when she saw that they were unconscious and vulnerable, she had to protect them from this mean guy.

Growling loudly, she lunged at Tomioka and started to attack him with her claws and kicks but he just dodged them swiftly as he thought of something.

'Long ago, someone else said the same thing, only to end up being devoured. A starving demon will eat anyone, its own brothers, sisters, parents. They're rich in nutrients. I've seen it more times than I can count.' He thought with an almost melancholy look as he dodged her attacks again and again.

'This girl has been badly wounded. She's using up a lot of energy to heal herself. And surely most of her strength was drained during her transformation, so there's no question. She's starving right now. She must have been craving a feast right from the start, even her own brother, but she protected him along with the other one and turned her attention to me.' Tomioka thought. He's decided. They're the ones.

Nezuko jumps to a tree and lunges at Tomioka again to make him pay for hurting Big Brother and Blue. He sheathed his sword as he dodged.

'I wonder if... Just maybe... These three are different.' Tomioka thought. He dodged Nezuko again before striking her at the side of her neck and knocking her out cold.

In Tanjiro's unconsciousness. Tanjiro is lying face down. Kie and his dead siblings surround him as they give him sad expressions as his mother caresses his head gently.

"We have to leave you behind, Tanjiro. I'm so sorry. Take care of Nezuko." She said softly.

In the real world, Tanjiro is still face-down in the snow as he wakes up with someone shaking him. He looked up and saw that it was Optimus.

"Are you alright?" He asked in concern.

Tanjiro nodded but when he caught sight of Tomioka, he quickly gathered Nezuko in his arms protectively, fearing for her safety but a hand from Optimus on his shoulder made him look at the prime in confusion.

"It's alright, he won't harm her anymore." Optimus reassured him as Tanjiro was still hesitant but he could smell that Optimus wasn't lying and relaxed a bit.

"Your friend is correct. I won't harm you." Tomioka said before he stood up.

"Get to Mt. Sagiri as soon as possible. Look for an old man named Sakonji Urokodaki. When you find him, tell him Giyu Tomioka sent you. It's cloudy, so she seems to be all right at the moment, but never let her be exposed to sunlight." He instructed them before he disappeared in a flash.

A few moments later, Tanjiro with Optimus and Nezuko, who has a bamboo muzzle on her mouth tied to a fabric around her head, returns home to bury his family. Optimus helped Tanjiro with the deed in silence as he gave him time to mourn. He can relate to him deeply over losing those he holds dear.

He watched in silence as Tanjiro prayed for his family to rest in peace. Optimus bowed his head, mourning Tanjiro's loss. Tanjiro is too young to go through such horrors at his age and Optimus has experienced death again and again when he watched his friends and allies getting killed in the war. He vowed to help Tanjiro to avenge his family from whoever killed them.

Finishing his prayer, Tanjiro finally stood up as he took Nezuko's hand, who had been silent the whole time. It's time to leave.

"Let's go."

Optimus nodded.

As the three of them headed down the mountain to Mt. Sagiri and to find the one that Tomioka told them to look for, Tanjiro looked behind them one last time to the home and the graves of his family. He promises... he'll come back after hunting down the one who killed his family... he'll make sure of it.

He, Nezuko and Optimus then started to head to the direction of Mt. Sagiri as their fates have now intertwined as a great journey will change everything they know.
______________________________________

(GURENGE)

Tsuyoku nareru riyuu wo shitta
Boku wo tsurete...! Susume!

(Optimus, who's human, and Tanjiro were seen back to back as the two open their eyes with the title saying "Demon Slayer: Transformers Prime")

Dorodarake no soumatou ni you

(Tanjri was thrown back as Optimus in his battle clothes got into a battle stance, ready to fight Sakonji)

Kowabaru kokoro furueru te wa

(The two were seen jumping back from a demon attack as they ran to fight the monster)

Tsukamitia mono ga aru
Sore dake sa

(Tanjiro ready his sword with Optimus readying his star saber as Sabito and Makomo were seen watching their progress)

Yoru no nioi ni "I'll spend all thirty nights"

(Zenitsu is seen running from Inosuke, who's giving chase)

Sora narindemo "Staring into the sky"

(As Inosuke grabs hold of Zenitsu, who's struggling out of his grip)

Kawatte ikeru no wa iibun iishin dake
Sore dake wa

(Kanao is seen with a butterfly on her finger, Genya is seen in a hallway and Tamayo and Yushiro are seen walking through a city street)

Tsuyoku nareru riyuu wo shitta

(Nezuko is seen in front of her family, her hair falling down as she turns around to see Optimus and Tanjiro)

Boku wo tsurete...! Susume!

(Muzan is seen as he turned around and an army of demons were seen as a silver haired man with razor sharp teeth and blood red eyes was seen wielding a blade glowing purple with his subordinates looking menacingly with the silverhaired man)

Dou shittate!

(A montage of Optimus, Tanjiro, Nezuko, Zenitsu, Inosuke, Bumblebee, Ratchet, Bulkhead, Arcee, Wheeljack, Smokescreen and Ultra Magnus, who are humans, were seen fighting different demons)

Kesenai yume mo tomarenai ima mo
Dareka no tame ni tsuyoku nareru nara

(Team Prime with Optimus and Tanjiro were seen fighting against Airachnid, Sasumaru, Kyogai, Starscream, Breakdown and Knockout as Nezuko is seen with the heroes helping them fight the evil)

Nando demo tachiagare

(Giyu and the other demon slayers were seen standing in front of the moon)

Sekai ni uchinomesarete makeru imi wo shitta
Guren no hana yo sakihokore

(Team Prime, Tanjiro, Nezuko and their friends were seen surrounded by demons as a montage of them using their signature weapons and blades against the demons)

Unmei wo terashite

(Optimus, Tanjiro and Nezuko look up to the sky as they turned around and smiled at each other and held hands)