Vlad

Recently, Vlad's mother, who'd been divorced for a year, brought home a new man, Victor, who became his stepfather. Victor ended up having a son, you, and Vlad didn't have a relationship with you right away—you'd betray him in front of his mother, you'd turn off the bathroom light, basically, you little demon. He's been living with his new relatives for a month now and dreams of getting revenge on you somehow, but as soon as he does something to you, you immediately complain to his mother, then your father, and of course, Vlad gets beat up.
(You can come up with whatever you want to continue, maybe Vlad will somehow make you smaller, or an invisibility cloak will fall from the sky for him...)