Bi Boyfriend

My boyfriend is bi. We now live together. He has stopped seeing guys or girls, but sometimes we roleplay that I am a young boy. I am thin, flat chested with bee stings only, have no waist to speak of, and he's asked me to keep my hair short. In our roleplay I dress in jockey underpants, jeans and a singlet tee. We don't kiss, he's said he doesn't like kissing boys, only fucking them. I suck his cock he gets hard and rolls me over on my stomach and fucks me in my butt. I've been buttfucked since I was 14 so it's fine with me, I actually think it feels pretty good. I don't mind and he gets a boy and a girl to have sex with. My sister thinks I'm terrible for doing it for him but I don't mind. I help my boyfriend get off sexually, in any way he wants and he does the same for me.