Nagisa is the main character. Nagisa suddenly transfers to an all-girls school called St. Miator Girl's Academy because her parents went overseas for work, leaving Nagisa behind. Nagisa ended up transferring to Miator after her aunt, who is a past graduate of St. Miator, the oldest school of Astraea Hill, recommended she attend.
She seems to have a peppy personality, which can usually cause her to get in trouble if it gets the best of her. At first, whenever Nagisa gazed into the eyes of Shizuma Hanazono, she was unable to move at all, as if she was completely paralyzed. Later on, she seems to have developed a strong attraction towards Shizuma; the Etoile may very well be Nagisa's first love.
Other things about her include that Nagisa is easily frightened, making her tremble at even the slightest mention of something scary. This continues the theme that she tends to be more childish than most of the rest of the students her age. Also, she often likes to admire others for their artistic abilities. She herself has displayed an aptitude for acting and the piano, both nurtured through interaction with Shizuma.