Setsuko Koike is a young and lovely nurse in the medical section of Shonan Special Disciplinary School.
Setsuko is considered an attractive woman with long black hair reaching her chest and brown eyes. She soon cuts her hair to chin length. Setsuko is usually seen wearing a nurse uniform.
Setsuko is a kind and timid woman. She's known the best of people.[clarify]
She was in love with Rokurouta Sakuragi. When he died, she tried to move on, beginning a relationship with Minakami Mario after he falls in love with her. However, after Mario becomes a criminal, she becomes worried about her future. As a result, she leaves him and gets married to someone else.
She has moved away from her family and is now living by herself because she was relocated to another hospital.