Spock is not certain why Jim is laughing. It happens with some frequency, Jim laughing and Spock being uncertain as to why, but he does not let it bother him as much now as in the past because he's more accustomed to Jim's easy laughter and assumes it's an indication of his enjoyment in these activities. Regardless, it doesn't last long before he's silenced Jim once again with the kiss.

Spock doesn't want Jim to pull away, but recognizes that he's doing so in order to strip off his shirts. In the brief time before he comes back to the kiss, Spock's attention drifts down his torso, his hands following his gaze.

Spock doesn't argue when Jim pulls him down to the floor, pausing before he moves over him to peel the shirts off over his head, both together to save time, and uncharacteristically let them fall in a mess to the floor before he moves down over Jim, leaning to kiss him but still just unable to keep his hands off of him, one hand going down to his waist to undo the button of his trousers.