Strap On

"On the bed slit" Adam's sister command pointing. Adam moved to comply but as he sat down his sister screamed "FACE DOWN ASS UP SLUT" and he hurried to comply.

As her bitch of a brother complied with her commands she smiled feeling giddy. She reached into her bag and pulled out a massive strap on fixing it firmly to her legs already feeling the wetness between them.

As his sister moved behind Adam he started to have second thoughts but it was too late as he sister slammed her fake cock into his ass without warning. The first thrust was amazing but before she did anything else she leaned over her bothers body and said a single word "Beg slut". Adam hesitated and so she grabbed his hair pulling his head back and said again "BEG SLUT". Adam swallowed and then said in a small voice "Fuck me", his sister though just pulled his hair harder and he said louder "Fuck me". "And what are you" His sister replied with glee at his submission. "Please fuck your slut master," He said feeling a great release as he did so.

She felt her body heat up and his words and started fucking him again harder. Looking down at her brothers back she could see changes already, his dick had shrunk and body mass seemed to be moving to his chest. Egged on by the changes his sister started slamming into his ass harder and faster as her dear little brother couldn't help himself but moan a bit with each thrust.