There's still something in him that's - not quite disappointed - it would be a different kind of disappointing if the hardest he could hurt her like this wasn't enough to be the right amount - but that backs off from some deep plunge it would have made, if this person had possessed Carissa levels of pain tolerance.

It's not most of his thoughts, most of it is on maintaining that pressure of his fingers, at the level that would have been, by the time she called out, slightly more than the optimal amount to arouse her most.

There's still something in him that's - not quite disappointed - it would be a different kind of disappointing if the hardest he could hurt her like this wasn't enough to be the right amount - but that backs off from some deep plunge it would have made, if this person had possessed Carissa levels of pain tolerance.

It's not most of his thoughts, most of it is on maintaining that pressure of his fingers, at the level that would have been, by the time she called out, slightly more than the optimal amount to arouse her most.  He does not just want her arousal, he also wants her pain, and between those two utility functions is that a compromise.