There is nothing you can do that I have not already done to myself

Watching Sollux move with that vulnerable, near pained expression, Dib reached up to brush his fingers through Sollux's hair. He gave wordless encouragement to go at a reasonable speed for him, while he tried not to hit his climax out of the sheer novelty of the sensation. He worried about Sollux actually injuring himself, but knew that his friend knew his limits and knew when to quit - something that he wasn't sure he could say was true about himself - so he'd definitely pull away if he'd hurt himself. He leaned up to nip Sollux's jaw while his hips continued to roll.