Older sister of Ryuji. Seen as a delinquent just like Ryuji by her father. She often lets Ryuji stay at her apartment when he needs to.

When Nagisa stays at her apartment, she catches Ryuji reading adult magazines and offers to give him some advice on girls. She reveals that she has been coming home late every night to create opportunities for Ryuji to make his move. Later, her apartment gets broken into and she gets knocked down by Akutsu, who comes looking for Nagisa.