It's a smart move on Kai's part, for sure, to add that bit of warmth into the situation himself. The blankets only help so much, and while Shinji isn't getting into too deep of a sleep, his drowzy mind is still being left an awful lot of room to reason why he's still so cold, still having trouble talking deep breaths. Having something as warm and real as another person nearby is enough to reel him out of that all too familiar drowning sensation, and into something that's becoming almost as commonplace.

Just... having someone there.

Not really giving the extra presence too much thought, Shinji eventually finds himself turned toward the source, curled up and pressed close into Kai's chest as he continues to doze.