Starry Sky is the story of the only girl at Seigatsu Gakuen, a school that specializes in celestial topics such as astronomy, horoscopes, and other topics related to these fields. Since the schools inception, Seigatsu Gakuen was an all boys school, but recently they've opened the school to girls as well...Thus, our heroine joins the school's astronomy section with her two childhood friends, Kanata and Suzuya. This is how she becomes the first, and only, girl of the school.
As she enjoys peaceful, fun days with her two childhood friends at school, her class gets a transfer student, and little does the trio know at the time, but his appearance ushers in a change for the group. The half French-Japanese transfer student is none other than Yoh, a boy the protagonist knew from childhood. While his transferring to her class was pure coincidence, he instantly favors protag-chan and makes it no secret he is utterly infatuated with her. At first, Yoh is cold towards Kanata and Suzuya, but slowly he begins to become part of the group, and in the process inadvertently begins to change the relationship between protag-chan, Suzuya, and Kanata. Yes, sadly, their days of peaceful friendship are changing with Yoh's appearance and feelings long felt begin to bubble to the surface.
The Starry Sky series features main characters based off of the astrological signs. In Spring features Pisces (Kanata), Capricorn (Yoh), and Cancer (Suzuya).