He can get that - he doesn't want to make people worry about him either, least of all the people he cares about the most. That's probably not something he can very realistically keep from happening altogether, though, but... the effort will be there.

"I know," he mumbles, as reassuring as he can manage. "I don't mind worrying about you, but mostly... you know," here he turns his head a little bit, nuzzling very slightly into Kai's neck as he does, "I just want to make sure you're taken care of."