The tone just made it worse, exponentially so. Blood ran straight to his groin in a predictable change of flow at the words, at the ground, at the smack that made his skin hotter and more sensitive than than it already was.

Spock took a few breathes--five seconds, six seconds--before he took his hand off the corner of the chair (there would be another opportunity to make his escape without just killing his captain). His thumb hooked under the elastic, and he shifted his hips enough to pull it down his thighs.