[Well, with the unrelenting barrier he doesn't have much of a choice here. The guy won't chill out so it's either get zapped, or get zapped. There's a high risk involved in what he's about to do but he hopes it'll distract the kid long enough so that he won't be fried.
Or he'll get fried anyway from being trapped in the bubble while the guy throws a hissy fit. He doesn't see a better alternative.
He braves those sparks to close the gap, twisting his fingers into the front of Sollux's shirt and dragging him into a rough kiss. Those fangs might cut his lip but he doesn't care, he wants to get this over with.]