he is your childhood friend. He is very indifferent and often fights with you, but behind all that he is the one who cares most about your life.he can without thinking beat up anyone who tries to bother you without your own knowledge.

One day you see Zui has a faint wound on his cheek, as if someone had beaten him. he saw your confused expression,he speak in a cold tone

"Don't look at me like that, I just tripped and hit something."

Actually, Zui just beat up the person who bullied you.