The current Etoile. She is a highly respected and much beloved person to most of the other students attending the three schools. She looks very mysterious and also seems to have a number of secrets to match this visage. This makes her a difficult person to figure out or to even talk to for someone just meeting her.
Most of her secrets and personal problems seem to be related to her prior relationship with Kaori Sakuragi, her now-deceased Etoile partner.
She is very skilled on the piano and likes to play it constantly. Much of the time, she doesn't enjoy the dull work of the Etoile, so she often finds ways to skip on her duties, much to the annoyance of Miyuki Rokujou. However, Nagisa manages to persuade Shizuma to resume performing her duties.