Blackmailed By Bf's Bully Big Brother

My boyfriend has the biggest cock I've ever seen and it's ridiculous that his big brother bullies him for being ''small". Clearly he just needs some stern words to knock it off, so I go to talk to him. I truly think he's only bullying my bf because he has a small dick and must be jealous... but when he drops his pants he has an GIANT cock?! I guess I understand how he could say my boyfriend is small, but it's still no excuse to be a bully. He wants me to touch it... ew! I pride myself on being a loyal and loving girlfriend but when he says he'll stop the bullying if I stroke him I do it. He then changes his mind and says he'll only stop if I suck him off, fine but I'm totally not enjoying it (I think?). Finally, I think I'm done and I've freed my bf, but then- like a true bully, he goes back on his word and now he says he'll only stop if he can fuck me?? That's blatant cheating (and with my boyfriend's family to make it even more taboo!), but I promised my bf I'd take care of the issue so I reluctantly turn around so the almost inhumanly large cock can stuff my petite pussy. I'll admit it wasn't the worst sex I've ever had, but he totally oversteps by giving me a giant creampie!!! At least it's over, no more cheating, no more bullying -- until I find out one more awful thing he did... FEATURES girlfriend x boyfriend/s brother roleplay, blackmail, cheating, bullying, reluctant but secretly enjoying it, POV, handjob, blowjob, sex in doggy, extra large dildo, huge creampie!