It'll make it harder for me to sleep if you can't sleep. [That's a pretty easy counterargument to grab for here, even if he knows neither of them is really going to press the issue anyway. He's not even averse to the suggestion on principle, given his sense of privacy was left behind somewhere in the early days of having to live in close quarters with dozens to hundreds of other people at any given time.

At least Ren turning around gives him the time he needs to recover himself (even if the laughter does get a bit of a side-eye), and after the few seconds that takes, he starts heading over to help look. That remark from Ren gives him the impression that he still doesn't know what he's going to get out, which means he looks a little surprised when Ren already has something pulled out basically by the time Shun gets over there.

After a moment, though, the surprise shifts to a more flat look, as if Shun wasn't quite sure he should've been surprised about it at all.] It's starting to feel like you've thought about this before.

[It can't be that different to when he was apparently noticing clothes that he thought would look good on Shun, and that wasn't even that long after they met.]