Sollux turns- quickly and frantically when he hears a suddenly splash of water nearby. He's a split second away from bringing out his trident when he realizes that it was just Jane jumping into the water. Crisis averted. He still has his hand over his collapsing and expanding bladder based aquatic vascular system though, out of sheer panic.

...And wasn't she wearing something different before?

Sollux looks to Tavros, a little lost for proper social direction at this point.