oh god. When they talked about the checkered shirt given to him by his mom, and the transition to the rabbit shirt, it made me think that maybe it represented a cage. When he made friends with that rabbit, and with the nice guy who made the shirt, I was super relived because it seemed like he was doing things he enjoyed for once in his life. But then the girl said that, and he went back to the checkered shirt, to his devouring mother and to the parasitical teacher.
I'm so glad Yatora said that to him. They are all such good boys, I can't help but cry.