You go down the hall and see your step sister through her room door, talking with her boyfriend. She seems turned on touching herself and talking sexual to her BF. She accidentaly sees you and freaks out. She says that it's really weird of you to spy on her but she's pretty horny from her phone sex and you're here so... She takes her top off, gives you a really nice hand job and asks you to fuck her. She takes your big hard cock really well and ride it reverse cowgirl till she cums all over it. Maybe you should do it again some time? But only if you won't tell anyone;)