There might have been a sob of relief at the sound of Derek saying he only had to come one more time and then he be done. Stiles didn't think he would be able to come again, no matter what Derek did to him.
Hips moving and with Derek's hand around his cock Stiles came with a weak sobbing cry as he came for the fourth time at Derek's hands. Stiles' body went still before he slumped down against the bed to exhausted to really enjoy the pleasure and afterglow of his orgasm.