This chapter will be like a Demon slayer x MHA crossover, but at the same time not really.
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Nanami PoV

"Nanami, Nanami... sweetheart wake up." I heared a voice call out to me, my eyes flutter open to reveal my mother in her hero suit.

"Nghhh... -yawn- Mom... why'd you wake me up... what time is it?" I asked as I rubbed my eyes and looked at my clock.

"Mom... its only 4:30 in the morning." I said to my mother.

"I know and I am sorry sweetie, but your father wanted to give you this." She then took out a small white envelope and gave it to me.

"... What is it, and why cant it wait till morning?" I asked as I grabbed the envelope.

"Yor father only told me to give this to you and nothing else, now I am off to bed ok, good night my kitty." Mom said as she gave me a kiss on the forehead.

"It's already morning mom." I said sarcastically.

"You know what I meant." She said as she walked out of my room.

"Ok dad lets see what was so important that you simply had mom wake me up at the crack of dawn?" I said as I opened the letter and here is what it said:

Dear Nanami (YN);

         Your father has told me alot of wonderful things about you, and he let me know that you are in dire need of your own blade, a weapon that reflects who you are, to continue on your hero training, If you wish to have a blade that can rival your father's Murasaki then come to Mt. Sagiri, where I -along with your father- will be waiting for you at its peak.
Sincerely:
Kamado Tanjirou

As I read the letter my smile grew larger, the one who wrote this letter was Kamado Tanjirou-sama, a genius smith who made my fathers indestructable sword, the blade that cuts down evil: Murasaki.

"I need to go!" I said as I jumped out of my bed and grabbed a few things like my phone, my iron gloves, and a map towards Mt. Sagiri.

After a few minutes I was ready to leave for my small journey, I then went down and saw a small packed bento on the table for me along with a note.

"'Dont forget to eat -love mom' thanks mom your the best." I said as I placed the bento on my backpack.

I then began my way to the train station, along the way there I was surprised to see Izuku, and he was equally surprised to see me.

"Nana-chan... where are you going?" He asked me.

"I can ask you the same thing." I told him.

"I-I am going to Dagobah Municipal beach." He told me.

"What?... but that place is full of trah Izuku, what are you even gonna do there?" I asked.

"Training?" He said.

"Fine... just done over exert yourself." I said to him.

"Dont worry I won't... hey you didn't answer me, where are you going?" Izuku asked.

"Mt. Sagiri." I told him.

"What thats a 2 hour train ride from here, what are you even gonna do there?" He asked.

"Hihi look at this." I then handed him the letter, his eyes then went wide and his jaw hung open as he read the content of the letter.

"W-WHAT KAMADO TANJIROU-SAMA IS WILLING TO MAKE YOU A WEAPON, I AM SO JEALOUS!" Izuku said as he clutched the paper.

"So you know of him." I gave a smug smile.

"Ofcourse I know him, he is a legendary swordsmith, he is the one they call 'the incarnation of Goro Masamune' he is famous for making alot of swords that can cut though almost anything, his most famous one though belongs to the 3rd ranked pro hero: Black mask, the sword that cuts down evil... Murasaki." Izuku rambled on.

"Izuku I know who he is." I said with a smile as he returned the paper to me.

"But how'd you get him to agree?" Izuku asked.

"My father knows him." I said with a smile.

"... Wait isn't your dad a parkour instructor at a gym?" He asked.

I then tensed up remembering that there are only a handful of people that knows who dad really is.

"Y-yeah... ummm... t-they were classmates in Junior High and college, they are also very close friends you see, so my father managed to convince him to make me a weapon." I said as my smile became crooked.

"Hmmm... ok then, that seems convincing." Izuku said with a smile.

"-sigh- Well I gotta go, bye Izuku! Goodluck with your training!" I said as I began to run towards the train station.

2 and a half hours later

I finally arrived in the station near Mt. Sagiri, there weren't any people there so getting directions would be difficult, good thing I brought a map with me.

"Hey you girl with the black hair." I heard someone call for me, I looked to my right and saw a girl with black hair that turns indigo at the tips, she has deep blue eyes and a butterfly clip was tying her hair in a high ponytail, she wore a loose Kimono with synthetic boar fur wrapped around her shoulders.

"Ummm... can I help you?" I asked cautiously.

"Your the daughter of that demon correct?" She asked.

"Demon?... HEY DONT CALL MY FATHER A DEMON!" I said angrily, my father may seem scary but he is a very nice guy, so when I hear people call him a demon I want to yell at them but I cant.

"But his strength... its so... demon like." The girl said with a smile.

"ITS HIS QUIRK YOU CRUELA DE VILLE WANNA BE!" I yelled in anger.

"WHAT DID YOU CALL ME! THATS IT YOUR GONNA F**KING DIE!" She said as she began to change, her whole body began to grow fur, her eyes became pitch black and a tail sprouted behind her.

"... YOU CALL MY FATHER A DEMON AND THEN YOU TURN INTO... THAT, WHAT THE HELL IS WRONG WITH YOU!?" I said as I put my gloves on and redied myself for a fight.

Somewhere ontop of the mountain
No PoV

On top of the mountain stood an old looking house, on the veranda sat 7 people 4 males and 3 females, they all happily drank tea together.

"You should stop your daughter Kenpacho-san, she is definitely gonna loose to my daughter." A man with black hair that turnyblue on the tips said, however he was slapped upside the head by a woman with long black hair with butterfly clips on the side of her head.

"Stop overestimating our daughter you thick-Headed man." She said.

"Why'd you hit me Aoi!?" He scream.

"Now now no fighting in my dear brother and dear sisters house please." A woman with long black hair that turned maroon on the tips said.

"Are you sure you want to have our son on this trial too Tanjirou, (YN)?" A man with long yellow hair asked.

"Yes... why'd you asked Zenitsu?" (YN) asked.

"Well... he can be a little-" Zenitsu started but was cut off by his wife.

"Uncontrollable, specially when his quirk activates." The woman said.

"Dont worry Nezuko, Nanami will be ok." A man with long burgundy hair said as he took a sip of his tea.

"Would you like more tea Tanjirou?" A woman with long black hair and purplish pink eyes asked.

"Yes, thank you Kanao... you look stunning today as always Kanao." Tanjirou said.

"Thank you as always." Kanao said with a smile.

"Please dont flirt infront of me you two, it makes me wish I brought Shia with me." (YN) said as he placed his head on the table.

Suddenly a white crow landed on Aoi's shoulder.

"Hello Shirona... yes... I see... oh really... that's amazing, I guess she really is his daughter." Aoi said seemingly able to talk to the bird.

"So what did it say, did Inari win?" the man with black hair and blue tips asked.

"Sorry Inosuke... she lost... quite fast according to Shirona." Aoi said with a smile.

"AHHH! -sigh- I guess we need more training... BUT MAKE NO MISTAKE KENPACHO ME AND MY DAUGHTER WILL BEAT YOU ONE OF THESE DAYS YAHAHAHA!" He laughed but was punched on the head by Aoi.

"Shut up... ok Shirona give this to her and guide her to her next stop ok." Aoi said as she tied a small note to the crows leg and tapped its beak as a faint blue glow coated the bird, it flew off to Nanami's location.

"You taught your daughter well." Aoi said.

"What can I say, it runs in the family." (YN) said as he took a sip of his tea.

Back with Nanami PoV

"Hmph! Dont talk a big game if you cant even dish it out!" Nanami said as she looked at the fainted figure of the girl she fought.

Suddenly a crow landed on her head and gave a loud caw.

"Hey get off me, whats the big idea!" She flailed around as the crow flew down of the ground and looked at her.

"CAW! NOTE! NOTE! CAW! FOR NANAMI (YN) CAW!" The crow said... I am not kidding this crow talked.

"What in the world are you?" I said as the crow flew on my hand and I took the note tied to her.

"Ok lets see here 'Hello Nanami, I hope Shirona didn't scare you, she is your guide up the mountain, and congratulations on your win.' Ok so your Shirona... so where to next?" I alsed the bird as she flapped her wings and flew.

"CAW! PLEASE FOLLOW! PLEASE FOLLOW! CAW! TRIAL UNDERWAY! CAW!" The crow said.

"Trial... oh so that was why she was picking a fight with me, it was a trial... oh dang... I should've gone a bit more easier on her should I known this was only a trial." I said as I looked at the unconscious girl.

"CAW! NEXT TRIAL! CAW! STRAIT UP! CAW!" The bird said.

"What about her?" I asked.

"LEAVE! CAW!" The crow said.

"Well if your sure." I said as I began my treck up the mountain with the white bird on my head.

5 mins. Later

I was on my way towards the top of the mountain when suddenly I felt a presence around me, I then took out my iron gloves and put them on ready for a fight.

"I know your there, come on out... unless your too chicken to do so." I said in a taunting manner.

"T-thats so mean!" A voice said as a boy with black hair that turned yellow at its tips said.

"Y-you didn't need to call me a chicken, I am already scared as it is!" He said in a shivering tone of voice.

"Are you the 2nd trial?" I asked.

"Y-yes I am the trial of speed and agility... m-my name is Nezuo Agatsuma... a-and the g-girl you f-fought earlier was Inari Hashibira... s-she was the trial of strength." He said nervously.

"Sooo... are you gonna attack or... something?" I said.

"Y-YES HERE I COME!" He said as he charged at me... with a sloppy stance and slow speed.

I began to dodge his every attack, was he really a trial... this doesn't even qualify as a warm up, suddenly his foot caught on a root and he face planted.

"A-are you ok?" I asked.

"Y-yeah!" He replied.

Suddenly the white bird flew towards him and landed infront of his face.

"Shirona... whats wrong?" He asked.

The bird -now known as Shirona- grabbed a large spider from a tree and showed it to Nezuo.

"GAHHHH NOOOO GET IT AWAY FROM ME!" He screamed as Shirona chased him around.

I slightly giggled from their antics, but suddenly Nezuo-san hit a tree vairy hard causing him to loose consciousness.

"Well... guess thats it for the speed and agility trial." I said as I began to walk further in.

"CAW! CAW! TRIAL NOT OVER! CAW!" Shirona said.

"What?" I asked.

Suddenly Nezuo-san stood up but his features were different from before, now he has a horn on the center of his forehead, his fingernails have large claws and lightning patterns were scattered all over his body as his eyes radiated white.

"Nezuo... san?" I said getting into a fighting stance.

In a sudden burst of speed he quickly closed the gap between us, he tried punching me but I was able to jump over his punch and knee him in the jaw... without breaking it ofcourse.

"Ok... this Trial... may actually pose a slight challenge." I said as I got into my stance, he did as well and we charged at each other with great speed.

Back with the adults
No PoV

The 7 adults were now relaxing on the beautiful veranda that had flowers and butterflies littered all over the garden.

"Nanami should be fighting my son right about now." Nezuko said as she and (YN) were playing shogi.

"Do you think she will be ok?... our son is very strong you know." Nezuko said as she placed a piece on the shogi board.

"Yes she will be ok... my daughter is not a pushover you know." (YN) said as he also placed a piece while taking Nezuko's piece.

"Hmmm... well thats game." Nezuko said as she looked at (YN) with a smile.

"Hey you almost got me a few time, you've improved Nezuko." (YN) said with a smile.

"Your smile really reminds me of my Onii-chan... I mean my brother... yet you hide it in an evil looking mask, why?" Nezuko asked.

"-sigh- Your just like your brother, asking a question like that... the answer is simple really." (YN) said as she helped Nezuko return the pieces.

"Whats the answer?" Nezuko asked.

"I just dont want my enemies knowing who I really am... I am not worried about my wife and daughter... I know they can take care of themselves... but my parents are old they are not as energetic as they use to be and my siblings have families now of their own... I dont want the people I love being targeted just because I was stupid enough not to wear my mask." (YN) said with a determined look in his eyes.

"Fair enough." Nezuko said.

Just then Shirona flew inside the veranda near her master Aoi as the two of them conversed.

"Oh... she really is amazing... good work Shirona... please guide her once again to her final trial." Aoi said as she once again touched Shirona's beak and the bird flew away.

"So... did our son win?" Zenitsu asked.

"Sorry, Nezuo got beat too... but he put up way more of a fight that our daughter... so good on both of you." Aoi said.

"Nezuo has grown strong... too bad he can only do it in his sleep." (YN) said.

"Were working on that." Nezuko said as she smiled lightly.

"However... the real battle will begin now... what do you think... Kanna?" Tanjirou said as a girl with long burgundy hair that was tied into a side ponytail, she also wore a red butterfly haori, she walked towards the adults with a smile.

"I think this will be a great match father." She said as she gave a beautiful and warm smile.

With Nezuo and Nanami
No PoV

Nezuo was knocked out by Nanami and was now sleeping in her legs, suddenly his eyes flutter open and saw Nanami looking at her with a smile.

"Hello there Nezuo-kun." Nanami said as Nezuo jumped in surprise and crawled away near a tree.

"Geez no need to be so on edge." Nanami said.

"S-sorry... I-I am not good with g-girls." Nezuo said nervously.

"Thats ok, you dont have to force yourself... now are you the last trial or..." she started.

"N-no... you still have to fight my cousin, her name is Kanna Onee-sama and let me tell you... she is very strong, she is the trial of skill, she is still undefeated up to this day." Nezuo said.

"Undefeated?" Nanamis asked.

"Y-yes... the trial of skill is the hardest trial to complete, only a handful of people were able to conquer it... your father -(YN) Oji-san- was one of them, he defeated Sakonji-sama the previous trial of skill, my father said he was amazing." Nezuo said.

Suddenly the white crow Shirona flew down and landed on Nanami's head.

"CAW! FINAL TRIAL! FINAL TRIAL! CAW! TO THE TOP! CAW!" Shirona said

Top of the mountain
4 hours later

Finally my treck is finally almost over, and let me tell you guys it was not easy to get here, I had to dodge logs that were trying to smush me, flying knives, darts, pitfalls, net traps, flying nets and alot more traps... but finally I was almost at the top of the mountain the only thing stopping me is large boulder, on top of said boulder sat a girl with Pink eyes, bright burgundy hair that was in a side ponytail, she wore a loose Kimono and a red butterfly Haori.

"Hello~" she said sweetly as she jumped down to the ground, and let me tell you this she was very graceful, with her butterfly haori she seemed to float down to the ground like an actual butterfly.

"Ummm... a-are y-you K-Kanna-san?" I asked nervously, this girl doesn't just look beautiful... she her strength feels like is on a whole different level.

"Yes I am, but let me introduce myself properly." She then placed her hands ontop pf pne another and gave a bow.

"Hello my name is Kanna Kamado the current Trial of skill, I hope we have a fun battle." Kanna said with a sweat voice.

"L-likewise." I said as I bowed as well.

"Very well." She said as she seemingly vanished out of nowhere.

Suddenly I felt a kick to my left arm as I went flying and slammed in a tree.

"Ara ara~ was that too unexpected?" She said as she proped her cheeks into her hand.

I the began to get up and in an instant I threw a stone at her, before the stone can reach her I used my quirk to teleport towards the stone.

In a flash of maroon I vanished and reappeared on top of her, I then did an axe kick but she caught my kick before it can reach her, she then looked at me and gave a smile.

"You have to do better that that~" she said sweetly as she threw me again on a tree.

With the adults
No PoV

The adults were secretly watching the 2 girls battle... however a certain black haired, butterfly clip wearing mother was not happy on what she was seeing.

"-sigh- Shinobu-nee and Kanae-nee are influencing Kanna in more ways than one and I do not know how to feel about this." Kanao said.

"Haha but you are also like that from time to time my dear... its kinda cute." Tanjirou said as he held his wife's hand.

"Get a room you two." (YN) said as he continued to watch the fight.

Back to the fight
Nanami PoV

Ok this girl is strong, she hits like a truck, has amazing speed and agility, and she is also so skilled that she was been only using the tip of her sheathed sword to fight me.

"Your amazing... tell me your quick... if you dont mind me asking." I said.

"I dont mind... my quirk is called 'skill tree'." She said.

"Skill tree?" I asked.

"Yes its the same quirk that my great great grandfather had, its a quirk that allows me to change my 'stats' for example, I want to be fast... I imagine myself having a video game skill tree and put it at speed, on the other hand if I wanted strength I put it on 'attack'." She said.

"So its like you can change your physical characteristics to match your opponent." I said.

"Exactly!" She said happily.

I had no other options but giving up is never an option for me, I need to somehow get a good enough hit in but how... I the looked below me and saw a bunch of pebbles, I grabbed a handful of the larger ones and smiled.

"I know what I have to do." I said.

"Ohhh... this seems like its going to be fun." She said as she unsheathed he blade to reveal a beautiful midnight black edge.

"Show me what you are made of." She said.

"Oh I'll show more than that!" I said as I threw all the pebbles in my hand towards her.

She looked at the pebbles and smiled, however I was already gone and will reappear on one of the stones, I thought it was my win but somehow, with someway she new were I would reappear and slammed the blunt side of her sword on my stomach causing all the wind on me to escape my body and fall to the ground.

I was about tp stand up but I was met with the sharp tip of her blade.

"I believe it is my win." She smiled

"No... I failed... It cant be... I am so sorry dad... I wasn't strong enough!" I said as I begam to cry.

"Thats not true at all." I heared a voice call out to me.

I looked to my side and saw my father along with the master smith Tanjirou along with some other people.

"You were amazing Nanami... you just dont have the correct mindset... and your heart was not on the fight." My father said.

"What do you mean dad?" I asked.

He then placed his hand on my head and gave me a pat.

"Thats for you to find out my dear daughter." He said.

"I don't follow." I told my father.

"You are here on Mt. Sagiri not just for a weapon... but training as well." He said.

"Really?!" I asked shocked by what my father said.

"Yes... to tell you the truth Sakonji-sama defeated me not once, not twice but three times before I defeated him and it was a narrow defeat." My father said.

"So... you trained here as well?" I asked.

"Yes... Sakonji-sama was kind enough to teach me the way of the sword, I trained here for months just to be able to truly polish my skills, and now it is your turn." My father said.

"So is this Sakonji-sama going to be my Trainer?" I asked with a bit of excitement.

"Hahaha no, Sakonji-sama is retired, you mentor will be... her." Tanjirou-sama pointed at the very girl who defeated me... Kanna-san.

"K-KANNA-SAN WILL BE MY MENTOR!?" I yelled with happiness.

"Yes my daughter will teach you everything you need to know to improve and find yourself." Tanjirou-sama said.

"Y-YOUR DAUGHTER!?" I yelled.

"Yes... I did mention my name is Kamado Kanna... it is my pleasure to meet you my new Tsuguko." She smiled at me.

"PLEASE TAKE CARE OF ME KANNA SHISHOU!" I said with a smile.

"Yosh~" she said happily.

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And done hope you guys like the little crossover, tell me if you did.

Thats all!

MigyTheWorld out PEACE!