Maeko had been somewhere on the outer edges of the conversation attempting to remember how to fold a sheet of green craft paper into a frog, close enough to be considered to be listenning to the joke but, having never been oficially invited to the conversation, far enough away that she was sure she wouldn't be bothering them with her presence.
The half-formed frog fell from her hands into her lap at Kou's outburst and then, after a few seconds thoroughly confused half-thoughts, flew from her lap to the floor as she stood up very suddenly.
She wasn't quite sure when Kozue had become hers to protect (and were she calmer she might have considered this an alarming development) but she apparently was. The times before when someone had done something like this she'd either been too distracted by trying to keep calm over something else or simply not present at the time.
Her mind didn't even register the possibility that the squares of paper Kou had left were anything to do with his rage. She was with Tom on the front lines in an instant, managing to remind herself that grabbing Kou's hair was probably a bad idea but still uncomfortably close. Her forehead was only just short of touching the back of his head.
"Yeah, what the hell?" She half-yelled, adding to Tom's statement and apparently adressing Kou's hair.