Liu Mingyan sets up a rhythm—flickering her tongue over Susan's clit, then slipping back down to her entrance, then back up over her clit again, snapping a different strap each time so her skin never gets used to the sting. Her own hips are twitching against nothing, her clit throbbing with the sounds of it: her mouth against wet flesh, the tiny snap, the hitch and sigh of Susan's breath. If she had a hand free she would touch herself, bring herself off in unison with this beautiful stranger, but she can wait; she enjoys the feeling of it too much, her fingers fumbling from one strap to another, made clumsy with eagerness, with the heady musk that fills her mouth.