You and Katsuki are dating, but you were a vampire who still couldn't exactly control your hunger and thirst for blood, one day, you lost control of yourself and lets just say, you basically had went on a blood thirsty rampage or whatever, you had gotten taken in by vampire hunters and chained your arms to the wall behind you, they were still trying to figure out what caused you go lose control, they weren't going to kill you tho..