Doctor Bisheer let out a screech as claws impaled his arm, just by the shoulder, and pinned him to the wall.

A growling, inhuman beast - namely, Rin Okumura, or, as he was now called, Experiment Zero - made crazed eye contact with the greasy haired man, before lashing out at the doctor's  face... using his teeth.

The animal was going to tear Bisheer apart with those fangs, and there was nothing anyone could do to stop him: he'd burn down anything in his path.

Eye's widening as teeth - dripping with saliva and snapping - dove towards his neck, Bisheer felt a split second of enlightenment where his instincts kicked in, all logic or higher thought long gone as adrenaline rushed his body. He slammed his free hand into Rin's jaw, sending the demon's gnashing fangs flying away from his windpipe. The scientist then turned his head away on reflex, cringing and protecting his face.

Unfortunately enough for Bisheer, though, the half demon still had momentum in his lunge, and so his misdirected attack landed somewhere else - the doctor's ear.

Fangs snapped shut around the fleshy tissue, biting clean through the cartilage like it was nothing. Rin roared through his mouthful in crazed victory, before shaking his head like a dog and tearing the chunk of meat straight off. Blood burst from the stump that was left, spraying Rin with beautiful crimson droplets.

The scream that left Bisheer was unholy.

..Rin enjoyed it all the more for that.

Licking the blood off of his lips, the half demon flashed a fang filled smile at the man, before taking his free hand and dragging it slowly, oh so slowly, against the wound he had already created. More blood pored out as Bisheer howled in agony, the boy's claws piercing deep into his skull.

Sopping up the man's screams, Rin brought his blood soaked fingers up to his lips and cleaned them off, one by one. His tongue curled around each finger, staining itself with Bisheer's copper tang. If the substance on his hand was anything but crimson stickiness, the action might've even been considered seductive. Rin didn't care about that, though, he was only thinking about how he could get used to the taste of blood - especially if it was Bisheer's.

Moving his hand to rest on the scientist's collarbone, Rin pressed his claws in deep, until they were buried up to the first knuckle - still totally unfazed by the animalistic screeches in his ears; in fact, he rather enjoyed them. Maybe, the bluenette thought, he had sounded the same when Bisheer tortured him?

The half demon shook himself out of his sadistic thoughts and proceeded to use his razor sharp claws like knifes, dragging his embedded fingers down the doctor's collarbone and over his chest, relishing in the sick squelching and tearing that allowed fresh blood to gush over his fingers. The half demon thought the red was a rather beautiful color when contrasting sharply with Bisheer's lab coat.

Finally, Rin was ready to kill this man - he just couldn't wait any longer. This sad excuse for a human being deserved death - now. Taking his hand out of the gaping, finger shaped holes he had created, Rin allowed his beautiful cerulean flames to light once more, relishing in the infinite power he felt. Bisheer screamed as the heat went up and up and up, until it was enough to melt metal; literally turning the skin on his shoulder to ash.

It started it gradually - because Rin was not feeling kind enough to make Bisheer's death quick. The skin swelled up and hissed until it reached a third degree burn, plasma bursting from welts which slowly began to ooze blood. Rin tensed his hand over the new wounds and clamped down, squeezing as he pushed his flames slowly hotter - and my, what a training experience! He could control the temperature of his fire! Bisheer should be proud!

The skin around the boy's hand was the first to turn black and crispy, slowly spreading in lines and cracks down the scientist's body, and Rin was enjoying this, enjoying this way too much, a crazed, hysterical laugh was making its way out of his throat as he watched the man burn, he was so, so happy, he was free, he was—

..he was a monster.

Rin's eyes widened as a sliver of his consciousness resurfaced, and he stumbled backwards, yanking both hands off and out of the man - who had gone into shock and passed out long ago. 

What was he doing? He—he really was a monster. Why was he enjoying that? No, he did enjoy it - he was free, it felt so good, he wanted to do it agai—wait! No!

Fighting the inner beast within himself, Rin struggled over to Kurikara as his claws slowly shrunk to small nubs. He grabbed the sword's sheath, bloodied hands trembling as flames burst brighter, protesting and fighting for their freedom. With a strangled sob, the bluenette slammed the sword closed, his flames sputtering and dying and locked up once more.

The half demon then fell to the floor, trembling as he stared at his hands. He could still taste the copper tang in his mouth, could see the blood soaking one forearm and the crispy blackness flaking off the other, and all of the sudden he was shaking, crying out no, no no no, because he was a monster - he didn't want to be a monster but he was, he was and there was nothing he could do. No matter how hard he tried to control the thing inside of him, he just - he just couldn't do it. He was a demon: he was a demon and he was going to kill everyone, no, everything he loved and if it was anything like what had just happened then he wouldn't be able to stop himself if he did.

I deserve to die, Rin thought, hands clutching at his head as he rocked back and forth. I'm an abomination - the Vatican need to get on with their execution.

He didn't notice when the door was cut open, didn't care when people in full body hazard suits came in and handcuffed him with blessed steel, didn't even flinch when he saw the mangled corpse of Bisheer getting lifted onto a stretcher - was he even alive? Probably not, but it didn't matter now - nothing did? Why? Because Rin was dead to the world. He felt nothing but self hate - and even that was disappearing into a terrifying numbness. This time he knew - one more push and he would loose himself for good. He was precariously balanced on the edge of sanity, on the edge of who he was - one more traumatizing event and the bluenette knew for sure that he would succumb to the tempting emptiness; he would forget who he was, just to stay safe from the pain. Even if it was selfish, he had taken as much shit as he could bear, and was this close to shutting down for good.

Too bad that one last shove came quicker than he had imagined.

His last thought as he got pushed into the familiar chamber of brown mist was something along the lines of, huh. So they're not going to kill me? ...pity.

And then Rin surrendered himself to the horrible memories, spending the night screaming and sobbing as his worst moments flashed through his mind's eye once more.

                                     ~•§•~

Rin didn't know exactly how long he was in there - in that cursed chamber - but it felt like millennia. All he knew was that when he came out, he wasn't himself. He wasn't Rin Okumura anymore; he didn't remember anyone or anything from his past. He was just an obedient, flame spewing doll, ready to be shaped and molded in any way the Vatican pleased, and they did just that - they bent their new toy to their will and made him the perfect weapon, and received not one complaint or refusal from the half demon.

And the girl he tried so hard to save? She died the night he was released from the chamber - by his own hand.

ive decided not to include a pairing like i had originally planned because i want all blue exorcist fans, no matter the ship, to be able to read this. i will be writing a separate story for blue exorcist - a soulmate au - but i think this story is better off without a pairing. as always, i love all my readers, and thank you for 14.5k views holy shit <33
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