When her mother passes away suddenly, Shinozaki Sumire finds herself alone and without a means to support herself. Out of desperation she turns to the message board Free Friends to earn some money. She develops a relationship with her first partner, Kaito, without realizing that they're much more than strangers...
His troubles trace back to a deeply seated complex: a hollow, yearning feeling brought on by the thought and sight of violets. Violets, or "Sumire", remind him of the sister he'd been separated from during their childhood when their parents had divorced. Only by losing himself in a woman's body can he rid himself of those clinging, nostalgic feelings.
Right before the school year begins, the mere reminder of the academy's famed violet flowerbeds (despite them not even being in bloom at the time) is enough to drive Kaito to Free Friends. A seemingly routine exchange leaves him completely unprepared for the girl waiting for him: an absolutely stunning beauty.