Aizetsu is the fourth twin of the four at Kimetsu Academy, he is different and quiet, characterized by being bitter and sad, with good grades, not boasting about his achievements and concentrating on his workshops.

He is part of the drama club and what fate has in store is that both were selected to imitate a couple in a play so they are practicing their dialogues and movements, although Aizetsu is a professional, the idea of kissing makes them both nervous because of what it implies.