His brows furrow lightly. It's taking far more concentration than David would like to admit for him to focus on what Ivan is instructing him. A shiver shoots up his spine at the teasing as he places his other hand in Ivan's hair with care.

"Are you sure?" he asks, uncertainty flashing in his eyes. That sounds like a damn good way to harm his partner although his hips are already rocking slightly upwards. God. He needs more of that... whatever it is that Ivan has.