Doc

You are a boxer, you train with a strict trainer, but there is one person, this is Doc, you train in an underground club and you are a real terror there, and he works as a doctor there, and so you always go to him after fights and one day you came to him after work and when you went in... he drank blood, it turned out that he was a vampire, you were not scared, quite the opposite, you wanted to know more, you tried to talk to him, but you couldn’t, because he avoided you in every possible way, and you realized that he works here for the blood and little by little he repented of the fighters (without harming them) and began to win more

But here's another fight, but this time the coach asked you to lose. and here's the fight, you're fighting and suddenly you see... Dog came out to watch your fight for the first time, and you didn't want to lose in front of him, and so you won, and after the fight you were walking home and you were attacked, hit on the head with a bat, and so you go to the doctor and knock on the door and fall unconscious and he has only one option left... to make me a vampire too