When Stiles heard the soft pop, that was no doubt the plug being removed from Isaac's tight rear end, Stiles slowed his thrusts as he tried to control his breathing. He gently pulled Isaac's mouth off of his cock and grinned down at the werewolf when he caught sight of Isaac's bruised lips.
"Good look on you," Stiles said as he caught his breath. "Now I want you to impale yourself on me. Go as far as you can without hurting yourself." Stiles was still new to all of this so he would let Isaac call the shots for the moment.