At school, Adrien was getting annoyed with Lila making a lot of lies about her trip to Transylvania where she saw vampires.

"Urgh! Again, with the fake trips" He thought.

Marinette sits with Adrien since she doesn't wanna hear that liar's lies ever again, "You could hypnotize her to make her tell the truth" She whispered.

"I could try that" Adrien grinned.

"But I am worried about the consequences," Marinette said.

"Like what?" Adrien whispered.

"Last time you said it only lasts 12 hours," Marinette said.

"Oh, right" Adrien replied.

"But she does know, right?" Marinette asked.

"Remember when I showed you that I'm a vampire? I threw a bucket at her and then scared her" Adrien said.

"Yes, I remember. But you do know she'll harass you about it" Marinette said.

"I know. But no one will believe her that I'm a vampire" Adrien held her hand.

"A badass vampire" Marinette corrected him.

"Yeah, my bride" Adrien joked.

"That's my prince" Marinette smiled.

While waiting for 20 minutes for Lila to be by herself, Adrien dragged her into the boiler room with his telekinesis, startling her.

"W-What are you doing?!" Lila gasps.

"You need to stop lying, Lila. It's getting on my nerves every day just because you want center attention" Adrien glared.

"Yeah? Any problem with that?" Lila replied.

"Popularity is not the answer Lila," Adrien said.

He then grabs Lila and bares her neck to bite her, "No! Please!" Lila begged.

"Scared?" Adrien chuckled, "I see you as a monster, Lila"

"Let me go!" Lila struggled.

"Not until you stop lying! I told you! The more you lie, the more they'll turn against you!" Adrien hissed.

"It's who I am, Adrien!" Lila smacked him.

Adrien just turned with a cold glare, his eyes having a red tint, "You're irresponsible, Lila. The reason I quit modeling is because I hate modeling. I hate you being a co-model. Popularity is never enough for you" Adrien said.

"You're gonna face the consequences, Adrien, I will through you and your precious girlfriend!" Lila tried to threaten him but Adrien lifted her with one hand.

"I don't think so! You're the one who'll face consequences! You've been a fraud for too long!" Adrien hissed.

"Stop hissing at me! You think your fangs can scare me?!" Lila yelled.

"Yeah!" Adrien then bites down on Lila.

"AAAAAHHH!!!!" Lila screamed.

Adrien pulled away but didn't drink her blood because hates liars, "Last warning, Lila"

Lila pulls away and placed some tissue on her bitemarks, quivering in fear.

"Fine, be like that but no one is gonna believe that shit" Adrien leaves the boiler room.

Lila groans and sat down in the boiler room, thinking about what to do.

-

After school, Adrien came home and glared at his father. He hissed lowly, whatever his father is thinking. Gabriel didn't say a word, knowing his son can hurt him again.

"I can hear your heartbeat, father. Don't try anything" Adrien morphed into a bat and flies up.

"Urgh, this is getting harder than I thought" Gabriel rubs his eyes in frustration taking his glasses off.

But then got startled when Adrien morphed back into a human behind his father, "Even if I'm back as a human, you better start treating me right!"

"Ah! Easy!" Gabriel gasps.

"And stay away from Marinette" Adrien added.

Adrien proudly walks to his room for telling his father off. He growled at someone he didn't want to see, "You just can't leave me alone, can you?" He glared at Felix in Adrien's clothes.

"Yeah, but these scratches you gave me haven't healed yet" Felix showed a patch on his cheek.

"That's what you get for ruining my life, three times" Adrien rolled his eyes.

"It was worth it," Felix said and took the comb to go back to his own hairstyle.

"You do know I can bite your neck anytime soon" Adrien crossed his arms.

"Which is why I brought backup" Felix held out a bottle of blood.

"Alright, thanks" Adrien accepts it.

"So, what did you do to school today?" Felix asked.

"Well, been listening to Lila's nonsense" Adrien replied.

"That bitch who you did not like touching you in modeling?" Felix said.

"Yes, that one. This time she lied she has been to Transylvania and seen vampires" Adrien said in a resentful tone and drank blood from the bottle.

"She was very disrespectful. Especially when she touched my hand on the train" Felix said.

Suddenly, the metal lockdown doors slide down on the windows and the doors. Just like the Simon Says incident.

"Aaahhh!!! No! Not again!" Adrien hyperventilates from this since this is his worst fear.

"We're trapped!" Felix exclaims.

He can see that his cousin looks much paler he fears being locked in.

"We need to get out of here!" Adrien bangs on the doors.

"Looks like I need to use something useful or you do the cataclysm," Felix said.

"NO!! I can't do that!" Adrien kept banging on the metal doors as hard as he can, "That bastard! He's preventing me from leaving!"

"Kid, calm down!" Plagg begged.

"We're trapped!" Adrien sat down.

Felix groans and sat down as well, "There has to be a way out"

"I'm not strong enough. I need more blood" Adrien looked at Felix.

"Alright. But make it quick" Felix bared his neck.

"I'm gonna attempted not to break a vein in your neck. Now hold still" Adrien sinks his fangs into his cousin's neck.

"AH!" Felix flinch as Adrien drank his blood.

Slowly to not kill this time. Breathing through his nose while sucking the blood from Felix's neck.

"Ahhhh. Oh, god" Felix groaned.

As soon as Adrien felt strong enough, he moved his mouth away from his cousin's neck. The blood in his veins began to flow through the skin.

"Time to bust the doors!" Adrien roared and smashed the metal doors down, feeling angry that he wants to seek revenge on his father, "This ends now!" He caught his father's scent which leads him to his office.

He punched the doors open to find his father inside, "You just couldn't let me live my teenage life, can you? I'm not your pet!" Adrien breathing heavily.

"So the metal doors didn't hold you?!" Gabriel was surprised.

"Yeah, trapping me and my cousin inside it like rats! I never thought you'd go this low!" Adrien clenched his fists.

Adrien became paler and his ears were turning pointy, "I'm gonna make you suffer!" He growled.

Argos tackled Adrien down but he knew he was too strong, "Adrien! Snap out of it! I did want you to teach your father a lesson but not like this!" He tried to reason with him but Adrien was no longer himself.

"RAAAAGH!!!" Adrien breaks free, his teeth all sharp.

"Adrien! Fight it! You're no monster!" Argos tries to get into him.

"NO!! I'm done hearing everyone telling me what to do!" Adrien began to mutate from all that rage building up in him.

"Oh shit!" Argos saw him mutate into a man-bat.

"What did you do to him?!" Gabriel demanded.

"You did! You made him angry!" Argos backs away.

"GGGGRRRRRRRR!!!!" Bat Adrien glared at his father.

Gabriel then tries to escape from his mutated son as Argos ran off to get help.

"The vampirism is out of control! I must do something" Argos tried to think of a solution.

He needs to create an antidote but sentimonsters don't have that kind of ability. He needs to try or his cousin will forever be lost within that monster. He can hear screeching from him and saw the pale mutated cousin fly out into the city, in this very cloudy sky with no sunlight.

"I better be quick or Ladybug is killed!" Argos ran to find a hiding place.

Mutated Adrien hissed hungrily for food to find but he can smell blood and hear frantic heartbeats all over the place.

"RAAAAAAAGH!!!" he roared once he saw Ladybug coming.

"Alright Bat creature! Let's dance!" She spun her yoyo.

Argos came rushing in and tackled Ladybug down before the bat creature could attack from midair, "Ladybug! That's Adrien! He's mutated!" Argos said.

"Get off me you traitor!" Ladybug kicked him off.

"I know but we need to team up before he destroys everyone" Argos pleaded.

"Very well, when it's over it's back to business! LUCKY CHARM!" Ladybug summoned her lucky charm.

Nothing came out, just like last time with Argos, "Nothing?! Again?!" Ladybug screamed.

"Shhh!!!" Argos covered her mouth, "He'll hear you!"

"What did you do to him?" Ladybug muffled through his hand.

"It wasn't me. It was his father. I swear! He got angry and he's not himself" Argos explained.

"SO MUCH BLOOD TO FEED!!!" Mutated Adrien cackled insanely.

"Cat Noir, pick up!" Ladybug tried calling him but he wasn't answering.

Plagg came in, "I'm afraid my kitten has been a scaredy cat"

"Great, just me and the bird. We need a plan" Ladybug groans.

"I need more time to create an antidote from a sentimonster" Argos said.

"There's not enough time, Felix! Adrien is gonna kill everyone!" Ladybug said.

"He's too fast, bug! Thanks to his father who can't treat him right, he had to take things way too far to destroy Adrien's happy life!" Argos argued back.

"This wouldn't have happened if your monster didn't bite him in the first place!" Ladybug argued and took out two purple macaroons.

"Eat this! Once you swallow it, just say power up!" Ladybug instructed him and ate her macaroon to become Cosmo Bug.

"Okay" Argos swallowed the macaroon, "POWER UP!" He became a neon-colored version of himself with bird wings from his back.

"I'll distract him while you do your thing. And fast before you're bird food!" Cosmo Bug yelled in his face.

"Got it!" Cosmo Bird nodded and took out a bat medallion and used his amok to merge with it so he can create a sentimonster bat once again, only this time as an antidote to reverse the effects on his cousin.

Cosmo Bug was distracting Adrien that is now interested in the bug, "Adrien over here!" She called out, "Exercising those wings too much will give a cramp!" Cosmo Bug taunted him.

"HRRRAAAAGGGGHHHH!" The mutated Adrien growled and flew after her.

"Follow the lead!" Cosmo Bug flew to Notre Dame.

But as he got close to the cathedral, he screeched that he can't go through since it was very holy.

"This should keep him at bay but I need to keep him distracted," Ladybug said, "LUCKY CHARM!" She again summoned and out came a blood bag, "A blood bag?"

She ducked when Adrien flew by, smelling the blood that drove him into a frenzy.

"I need the charm to fix the damage and distract him. That blood bird better be ready soon" Cosmo Bug said.

Adrien tackled her and tried to bite the bag of blood, "Adrien! NO! It's me Ladybug!" She struggled.

"La....dy...bug?!" Mutated Adrien spoke through growls.