I know this is not incest, but as a young boy i had oral sex with both of my step brothers. My older step brother is the one that showed me all about jacking off and one thing lead to another. we would be jacking each other off and the first time he started sucking me and it felt awesome and at the time his dick looked so huge and taste that I could not help myself from wanting to suck his dick and taste his cum. My very first time sucking him, he shot his load down my throat and every time after that. He would also suck me and swallow my load. I guess you could say that he was the best step brother a guy could ask for.
