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"Jessica, come with me." You say firmly. Jessica trots after you obediently, to where you left your sister standing blankly. "Alright, Beth, I want you to suck on Jessica's tits."

Your sister grins and moved towards her friend, practically ripping her shirt and bra off before diving in and sucking on her breasts, nibbling the nipples. Jessica wrapped a hand around her head and moaned, stroking her hair and whispering encouragement. You sat down on the sofa and watched, your dick slowly growing harder.