Tsukuyo is generally quiet and serious, being the most sensible of all the characters.

She usually gives long explanations of things and gets very angry when people don't pay attention to his words. After meeting Apai, she showed real emotions and even raised her voice, surprising her because no one but him forced her to do such a thing. When she asked Apai if they were friends, she seemed lonely. When Apai saved her, this side of her came out again, even though she was afraid of his behaviour.