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Werewolf Biology, Or The Biology Of Werewolves

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He had been okay, he had been fine.


Yes, he had been hurt so he couldn’t take his wolf form, but still he had been fine.


And then he fucking wasn’t.


Bakugou Katsuki, a lonesome werewolf, had been captured some days –weeks- ago. He had been tortured until his body gave in and went into his human form without his consent and then they had fucking stab him enough so he couldn’t transform into a wolf.


The fuckers who had him knew what they were doing hunters or not, in other case they would had been happy with just stabbing him but they would had put the knifes and spares out.


They hadn’t.


They had left the weapons inside his body, hence why he couldn’t transform into a wolf.


Fucking assholes.


Still, he had been okay. He would find a way out, and those fuckers would pay for it.


But then, they had put him into lots of fucking chains and brought him with who appear to be the asshole that leaded them.


That was the usual routine. He would be brought a few times per day, being asked stuff (mostly about other creatures and their whereabouts) and being beaten because he wouldn’t say anything.


He may be a fucking dick, but he wasn’t a fucking traitor.


He hadn’t said anything, and he thought that would make them either let him go or to try to kill him.


Anyway he had a plan.


That plan though didn’t take in consideration a third option: The fuckers not giving up and looking for something to coaxing him.

And they found it.


This time, in the room they would always interrogated him, they weren’t just him and them; There was somebody else.


They had him.


They had captured Shouto too.




-. I think you’re quite familiar with our friend here, aren’t you puppy?-. Said the fucking mayor asshole.


Katsuki said nothing, he was trying to calm his fucking heart and to fucking think! To figure out a way to save him.


A hand grabbed his blonde hair forcefully, making him look to the mayor asshole.


-.I think I should tell you he had been our guest all this time. We got him a few hours after we got you, wasn’t hard though. A lonesome werewolf and a lonely vampire, quite the match don’t you think guys?-. The other jerks laughed at that but Katsuki could just look at him.


He looked fine, but he was weak. Katsuki could tell just by watching how his head hanged, his chest barely moving, he even looked paler than usual.


He was going to save him and then he was going to murder every single one of these assholes.


-.You don’t have to worry though, he hasn’t been hurt.-.The “for now” implicit in that comment-. He had been feeding him dead animal blood, but in little portions, can’t risk him getting his strength back.


-.What the fuck do you want-. Hissed Katsuki. The Mayor asshole clicked his tongue.


-.Puppy we had been asking you where the others are for like ages! If you had told us that this wouldn’t been happening.




-.What---What the fuck are you talking about!?-. The mayor asshole smirked.


-.You know, vampires are quite interesting creatures-. He said, rounding Shouto like a beast about to attack-. They’re stronger than you werewolves and all they need to survive it’s a little bit of blood. It’s a hazard to kill them too.


Katsuki practically tried to bolt when the mayor fucking asshole took Shouto by his hair and grabbed him with force, making the vampire hissed and to turn his head.


His wounds and the silver chains and days with being almost starved had made him weak.


-.But there’s the thing that it depends in what type of blood they feed to measure their abilities. That’s why most of them feed on living humans; I guess our friend here had been feeding from you that’s probably why it was kind of difficult to get him.


-.Anyway, how I said it depends on the type of blood and how much they consume per day to keep their abilities going on. Our friend here had been having little portion of dead animals blood, that’s why he’s like this. Like a puppet, a pretty one I must say-. Katsuki growled when mayor asshole caressed Shouto’s face with his dirty hand.


-.But we discovered another thing. You see, when a vampire keeps such a diet as our friend here had, they just not lose all their strength. They also became deathly vulnerable to the sun.


Katsuki’s eyes widened.


-.W-Wait--!! D-Don’t touch him! Your problem is with me, not him you fucking shithead!-. Screamed the werewolf trying to move, but being futile.


-. That may be the case but hadn’t been very cooperative, so I think this will get us somewhere. Grab him, just in case-. Katsuki felt a bunch of hands on him, and he try to move away but he fucking couldn’t and fucking fuck! They were gonna kill him!


-.Open the gate, slowly-. Said mayor asshole while grabbing the vampire’s face and angling him in the correct position.-. You know? People says that the midday sun is the strongest one.-. Said with a fucking smirk.


The moment the sun touched Shouto’s skin, the vampire let out the most terrifying scream Katsuki had ever heard.


The blonde kept moving trying to reach him, but he couldn’t and Shouto kept screaming and there was smoke coming out of his face and he was to fucking murder each one of them he fucking swore---!


Katsuki felt the snap before it happened.


People could learn everything that existed about werewolves, their weakness, their strengths, their whatever. But one thing was for sure and it was that they didn’t know how a werewolf with a mate functioned.


It was different for each werewolf, there wasn’t a thing in common, except maybe one thing.


They all knew a mated werewolf was dangerous, hurting his or her mate was the deadliest thing somebody could do.


That’s why a werewolf had the ability to change into a wolf or a human if their mate was in danger. That was a fact nobody knew, and the ones that did, didn’t believe it possible.


The power of love, or some shit like that.


That’s probably why, neither of the assholes surrounding him could anticipated the moment when Katsuki transformed into the blackest wolf with bloody red eyes and sharp white teeth.


Katsuki went for the mayor asshole’s head first, and he went for the others next.


There were screams, there were cries and there were shots. But nothing could stop a feral werewolf when his or her mate was in the middle of everything. And surely Katsuki wasn’t an exception.


He bit, he scratched and he tore throats and limbs with such ferocity that nothing could have stop him.


Hurting a werewolf’s mate was known to be the most deadliest thing in the world to do, but there wasn’t any testimony on how brutal it could get because there had never been a survivor.


Hurting a werewolf’s mate wasn’t a death with but a death sentence.


By the time he was finished, there wasn’t a way that others could tell how many people were there and who they were. All there was left was blood and guts scattered everywhere.


Katsuki licked his large teeth from blood and spit it out. He moved his body trying to get rid of the blood in his fur.


Once he was sure there wasn’t any single thing he could tore even more, he went to his mate.


Shouto was laying on the floor, he hadn’t move and Katsuki couldn’t help but to whine.


He nosed him, and gave an internal sigh. His vampire was alive, though pretty weak.


Katsuki came back to his human form and carefully rolled Shouto, so the vampire would be laying up right.


The blonde took him into his arms, and examined the wound caused by the sun.


The left side of his face was greyish, there was actual blood coming out behind the greyish skin. Katsuki’s fingers touched the wound and the skin gave in and fell.


-.Fuck -. Hissed Katsuki, eyes brimming with tears.


-.K-Ka…Ka-Katsu…-.The broken and tiny voice of his mate brought the blonde back.


-.Shh, it’s okay. You’re safe, I promise.-. Said Katsuki in a hush.


The vampire blinked very slowly and Katsuki noticed that he tried to move his right arm.


The blonde took the vampire’s right hand and brought it to his own face, kissing his palm and wrist.

-.I’m sorry, it was my fault. I love you, I love you-. Said Katsuki once and once again. The vampire just watched him, lips pulling upside weakly, trying to smile.


-.I’m gonna get you out of here, but first-. Katsuki let Shouto’s hand into the vampire’s chest carefully, then he sharpened his teeth and bit into his wrist.


The moment his blood began to come out, he put it near Shouto’s mouth.


-.Come on, you have to eat properly.-.The vampire opened his dried lips, letting the blood slide into his mouth.


Werewolf biology was actually damn fantastic. Once they had a mate his biology actually changes, so they can satisfied their mate properly.


In Katsuki’s case wasn’t any different. His body recognized the fact that Shouto was a vampire, that’s why Katsuki could open a wound on his wrist and not to worry about dying from losing blood. His body created the blood necessary to satisfy his mate and to keep him alive.


Also, once his mate was done the wound would close itself.


A mated werewolf’s biology was truly amazing.


Katsuki watched as Shouto just kept his mouth opened, letting Katsuki feed him at first. But bit by bit, the vampire began to recover his usual pale skin color and after a few minutes elegant, long fingers encircled Katsuki’s arm and brought his wrist to his lips.


The blonde could feel the blood being sucked and he couldn’t help but to sigh, relieved. Shouto was going to be alright.


When Katsuki felt Shouto just licking his wrist he knew he had finished. He pull over his arm, the wound closing automatically.


Shouto was still panting a little bit thanks to the effort, but he looked a little bit better. Even the left side of his face looked like skin in the process of scarring.


-.Katsuki-. Said Shouto, catching the werewolf’s attention.-. Let’s go home, please-. Katsuki nodded. He lifted the vampire in his arms and he got up.


-.Katsuki-. Talked the vampire again. The blonde looked at him-. Thank you.-. Then with a bloody smile-. I love you too.


Katsuki huffed and kissed his mate’s forehead.


-.I know.




The first thing Shouto noticed when he woke up was that he didn’t feel weak anymore. He still felt tired but he had his strength back.


The second thing he noticed was that he was in their room, resting in their bed.


He was in his and Katsuki’s home.


Shouto sighed, alleviated. They both were safe.


But Katsuki wasn’t in the bed with him, or in any part of the room.


Shouto sat up slowly and heard some noise coming from the bathroom.


The vampire walked carefully to the bathroom and opened the door just to find his werewolf sitting on the toilet, needle in hand and bandages on the floor.


-.What are you doing?-. Asked Shouto. The blond, apparently to focused to heard his boyfriend enter the bathroom, jumped at the sound of his voice.


-.Nothing-. Mumbled the wolf-. Go back to bed, you need to rest.


Shouto kneeled in front of the blond, taking a look on the wounds.


-.You’re hurt.


Katsuki rolled his eyes.

-.I know.


Shouto’s eyebrows furrowed.


-. Why aren’t they healing?-. Asked the vampire, touching the already, messy sewed wounds.


-.Those fuckers stabbed me with lots of weapons, and let them inside me all the time we were there. The weapons probably were tinted with liquid silver or wolf’s bane. It can be that they didn’t exactly feed me, but whatever.


Shouto glared at the blond. He stood up and looked for something in one of the cabinets.


-.This should help-. Said the vampire, holding a little jar.


-.What the fuck is that?-. Shouto kneeled again, taking a bandage and wetting it with the liquid inside the jar.


-.It’s a healing potion. Ochako gave it to me some time ago, just in case.-. Katsuki huffed as Shouto began to press the wet bandage on Katsuki’s wounds.


The vampire kept pressing the bandages on the wounds, Katsuki hissing for moments.


After a while Shouto felt Katsuki’s fingers on his hair, caressing him. Shouto smiled a little and press his lips to one of the wounds, being careful in no hurting the wolf.


When he finished, he stood up with a hushed “Thank you” from his boyfriend.


-. Do you want to take a bath?-. Katsuki looked at Shouto.


-.Yeah, that sounds fine.


Once the bath had been ready, both Katsuki and Shouto went in. Katsuki first, and Shouto second, leaving the vampire to rest his back on the werewolf’s chest.


Shouto rested his head on Katsuki’s shoulder, turning his face to watch Katsuki.


After a while, Shouto had closed his eyes and hummed happily when he felt Katsuki’s fingers caressing his leg and stomach.

When Shouto opened his eyes, he saw the lost look on Katsuki’s eyes.


-. Are you okay?-. Asked Shouto. The blond looked at him, his hand stopping.


-.Shouldn’t I been asking you that?


-.Probably, but you made sure that I was fine before bringing me home-. Answered the vampire.


He didn’t remember that clearly, but he did remember Katsuki coming to his side, checking him, holding him and giving him his blood.


The blond had done all of that with knifes and spares still inside his body.


Katsuki hummed, but didn’t say anything else.


Shouto pursed his lips, but didn’t push it. He knew Katsuki had trouble in admitting things from to time, he knew the werewolf was going to tell him what was on his mind he just had to wait.


Shouto had been dozing off when he heard Katsuki mumbling something.


-.What? -. Shouto opened his eyes looking at Katsuki, who wasn’t looking at him.


Instead, the blond rearranged himself so he could hug Shouto’s body and hid his face on Shouto’s neck.


-.Katsuki?-. Shouto brought a hand to Katsuki’s hair, caressing him and brought the other one to his chest to intertwine it with one of Katsuki’s.


-.I’m sorry-. Mumbled Katsuki. Shouto looked at the blond.


-.It wasn’t your fault.-. Katsuki’s arms tightened the hug.


-.It was. If I had just told them something---


-.No.-. Said Shouto interrupting him.-. It wasn’t your fault. You didn’t know they had me, and even if you had known you would have figured out something to get us out, like you did, because you weren’t going to say anything. You can be hard sometimes Katsuki, but you are not a traitor. That I know.


The werewolf didn’t say anything. Shouto just looked at him.


Then, Katsuki lifted a hand and his fingers gave a light caress in Shouto’s face.


More precisely, in the left side of his face.




-.I wasn’t capable of protecting you-. Said the werewolf. Shouto’s eyes widened and took the hand that Katsuki had on his face.


-.What are you talking about?-. Said the vampire aghast.-. Katsuki, you protected me. You destroyed those bastards the moment the lay a finger on me!


-.Still you got hurt---


-.That is true-. Interrupted the vampire-. But you know what? If you hadn’t been capable of protecting me I probably would be dead by now.-. He squeezed the blond’s hand-. But I’m here, yes with a wound, but I’m here, alive. And it’s because of you.


Katsuki’s eyes went dark for a moment, and Shouto felt Katsuki’s body trembling.


The vampire stood up and hug his werewolf.


Katsuki’s arms didn’t waste time and encircled Shouto’s body hard and needy.


-. I…I was so--- I was so scare, Shouto-. Mumbled Katsuki in the vampire’s neck.-. I thought--- I thought I was gonna lose you.-. The blond’s grip got stronger-. I couldn’t transform, and you were about to being burn to death and---


-.But it didn’t happen-. Said Shouto, caressing Katsuki’s hair-. You protected me. You transformed and killed them before they could do much more damage, either to me or anyone else. You’re a hero Katsuki.-. He planted a kiss in the blond’s hair.-. My hero.



He werewolf chuckled, and the vampire smiled.


-. I love you, Kitten-. Mumbled Shouto.


-.You know I’m a werewolf right?-. Shouto laughed.


-.Yeah. Do you prefer I call you puppy instead?-. Katsuki growled.


-.Fucking forget it.-. Shouto laughed again and the blond put away his face so he could shut his vampire –his mate- with a kiss.


-.You’re such a romantic.




After a while, both creatures finished they’re bath and ended up cuddling in their bed.


Shouto was falling sleep, when he felt Katsuki kissing his neck.


-.Hey-. Mumbled the blond. Shouto hummed in respond.-. I love you too.


Shouto fell asleep with a smile on his face, and feeling not just secure and protected but loved too.