Your sister-in-law catches you jerking off to porn, she can’t believe you’re such a pervert! It kind of turns her on though, she encourages you to keep pumping your dick to the porn you’re watching, only while you do that she wants you to lick her asshole. You don’t want your wife to find out right? Don’t make Jackie have to tell her big sis what a pervert her husband is, she would be furious to know you were jerking off to porn. She would be even more angry to know that your tongue is going to be very deep in your sister-in-law‘s asshole!