Kaworu would have let them all change shirts, though he didn't think of it himself as, unlike Paul, he's not a sweaty creature due to being both an angel and much more prone to being chilled than overheated.

Likewise, he doesn't usually eat much, having a small and sensitive stomach that doesn't require much nutrients to make his body function. However, this morning he feels oddly... hungry. Perhaps this how humans feel when they dramatically declare that they are "starving". So he finishes more of his omurice than is typical and even drinks all of the juice that Paul gave him.

Then he promptly drops his arms onto the table, puts his face in said arms, completely unconcerned that this is right next to his plate. "Okay, we can go back to bed now."