Forbidden fruit of fucking
Her parents don't like this teeny's new boyfriend and forbid her from even seeing him let alone having some erotic shenanigans. That's why she decides they need to have sex asap and once the chance presents itself she finds herself on her fours getting fucked from behind right on the floor. Oh, what a great feeling it is to do something so pleasant and know it would make her parents just flip if they knew she was fucking this guy like that.