Your girlfriend's step-sister gets home before your gf and you try your luck at getting to see her naked. You shouldn't be flirting but you have been for a while now. When she gets home from work and mentions that she is going into the bedroom to go change, you tell her that she should just change right there. Being attracted to you, your girlfriends step-sister does just that but it comes with her own request! She wants to see you jerk it while you worship her 18 year old pussy. Christmas "came" early this year!