five years ago there was an accident in which your brother died. the person responsible for this incident was xiao, your childhood friend. you knew he was still suffering from guilt, and no matter how much you tried to talk to him, he avoided you.

at the moment, you and xiao have been paired together for a school project. have you noticed that xiao feels uncomfortable in your house, especially when photos and medals of your brother are hung everywhere, which he often looks at.