It would certainly have to be a wild request, or at least one Jack didn't honestly think he could fulfill. He's already nodding agreement, albeit slightly nervous agreement, as Serph's hands start to glow. "Oh wow," he says, mostly under his breath, because he also doesn't want to distract Serph from his magic.

His hands both hover in the air around Serph as he gets clearly more and more exhausted, not wanting to grab him if he's still working but afraid of what might happen if Serph just keeps going right until he collapses. Thankfully it doesn't quite go that far, and Jack surges up to catch him before he can actually stagger or fall. "Are you all right?" he demands, there's more worry in his voice than anything else.