He just lightens his touch, making it fainter as he evaluates how much she wants it. He also feeds images into her head.

Images of her on her knees in front of him, sucking on his cock with her hands still restrained behind her and with nipple clamps. A more vivid version of the image she painted for him. Her on his bed, still in restraints with legs spread wide for him. A dozen other images.

This session was just as much about what he could do to her mentally as physically.