Sein Kouzuki

Оригінальне ім’я: 皇月セイン

Kouzuki Sein is a member of Princess Rose Club and Himeno Karen's right-hand man. Being Karen's childhood friend, she had always treated Sein as a younger brother. Although Sein has showed his affections for her, Karen is too shy to accept it and often tries to turn away, though she too has feelings for him.