[ Easier to continue with gestures than anything else, and no need to make Sylvain spend energy he may not have on conversation. He sets the waterskin down nearby in easy enough reach for the currently more feverish one of them, then shifts to pat between Sylvain's shoulders with one hand in the universal gesture of move over. With the rock there it'll be a little difficult to wedge himself in without a little more space to do so first.

And sure, Claude could just stretch out in front, but that might invite being held rather than the holding he's planning on doing. Instead he'll slip into whatever space is vacated to lie down in slower motion than he might normally and with a wince only to himself as the wound on his back protests. Still worth it, and not enough to dissuade him from eventually getting to the point of being able to wrap an arm around Sylvain to pull his back towards his chest in a gentle suggestion, and while letting his hand rest on the other's chest to hold onto if or when it's needed. A bit more shifting, and then Claude stretches his other arm out to let Sylvain use it as a pillow. ]

You think it'd help if we just pretended we were somewhere on a floor in Abyss? [ Probably not but that's the closest underground option he can think of quickly, and then it makes it easier to heave a faux pained sigh for whatever it adds. ] On second thought - somewhere and somehow Yuri knows I just slandered Abyss by comparing it to this place and I'm sure he's already mad about it.