We had a thing, my step Brother and I, a secret, a well kept personal taboo secret. But we swore to each-other that it won't happen again, ever! Unfortunately that's what we tell to ourselves every time after we have sex. We know it's forbidden and gross for a step brother and step sister to fuck, but we just can't resist to each-other, there's this magnetic attraction toward each other and we don't know and probably don't truly want to stop it. I came to him to tell him that we really have to stop right now, that I intend to find myself a boyfriend and forget about this weird part of my life where I was in an relationship with my own step brother. But... the inevitable has occurred and while I was presenting arguments to him about why we can't continue, he was convincing me to do it at least one more time! I refused and he asked me to see my tits once more, and, knowing how much he likes them I thought it's no biggie and showed him a bit of my boobs. That was the beginning of the end. Once I saw that the throbbing boner in his pants I knew I want to suck it. Badly! I was drooling for it. I thought once more doesn't count, so I got in my knees and started sucking that cock like I never sucked it before. He felt how horny he got me and made me deep throat it to the balls until I gagged and saliva was drooling out of my mouth. Then we had sex, I couldn't say no, my pussy was so wet and now I simply didn't care anymore that he's my step brother. We fucked a lot, missionary and doggy, I had three orgasms until he got too close to the edge. I got in my knees again when I heard he wants to cum on my face. I smiled, looked him in the eye and encouraged him to splosh it all on my face and glasses. And he did it! When I opened my eyes again my face was soaked in cum, it was dripping on my chest already. I told him: you wanted this, now don't ever think to cheat on me, we have a thing here, between us!