Chiaki's run out of things to do herself and has gone in search of fellow shipmates. Onc she sees Ranka at the lounge, she sits in a chair near the wall to watch.

She claps after the performance, perhaps not aware that she's drawing the occasional stare from passersby, or at least trying not to notice -- her belly is pushing out visibly from under her shirt, buttons straining. She really should have picked a better outfit to wear upon leaving home.