SYou walk into your sister's room to find... BOTH of your sisters masturbating together on the bed. You're frozen in shock, watching at the door until they realize you're there. "OH MY GOD GET OUT OF MY ROOM!" They beg you not to tell anyone, but you know an opportunity for blackmail when you see one. "Fine, take out your cock then. Is that what you really want? To fuck your sisters? Then let's do it." They begin taking turns sucking your cock while they touch themselves, moaning and dirty talking to you. They seem strangely comfortable, and begin to beg you - almost daring you - to fuck them. They let you take turns in their pussies, and lick each others cream up off your dick before begging you to cum in one of their tight pussies while the other one watches "I want to cum with BOTH of my siblings" one of your sisters moans "I can't believe I'm having a threesome with my sister AND my brother!"