Being held down by someone so physically strong is a turn on, and combined with the lips on his cock it's no wonder he can't keep himself quiet. He would have loved to have pulled on their hair, but it seems there is none to pull. He settles for gripping their shoulder hard instead, and when they let go of his hips he can't hold back.

If they seem to be in distress he'll stop of course, but right now he needs to get off. His hand slides to the back of their head where he pushes them down with every thrust upwards of his hips, and his breathing soon becomes shallow and strained.

"Ah... you are doing wonderfully..." His thumb caresses the nape of their neck as his hand smooths down their back, blunt fingernails digging into skin. He's breathless, biting his lip hard as he edges ever closer to release. If Nimbus doesn't want him to finish in their mouth, now would be the time to signal as much.