You walk in on your sassy Sister-In-law taking naughty photos in a lacy bodysuit, you don't know why but you can't take your eyes away from her, and when she notices you she's shocked...but has something in mind to convince you to not tell your wife the naughty things she gets up to when she's over. Your Sister-in-law begins to seduce you, using naughty words and playing on your hidden desire for her; once your cock is straining through your pants she asks you to fuck her, promising no risk...but she's lying, your Sister-in-Law is fertile, on no birth control and you just came inside her. Now you have another secret to hide from your wife.