Individual fragments of human emotion usually take the form of flowers called "Fragments," and those with enough of them can become "Reflectors," beings that wear specialized rings that allow them to connect their thoughts, memories, and emotions to people whose sentiments waver. Reflectors wear blue rings to safeguard those who are falling into depravity by keeping their Fragments, and red rings to prevent negative feelings by stealing the Fragments of those who are starting to acquire acute woe. Ruka Hanari, a transfer student, is shy and introverted, which makes it difficult for her to socialize with others around her. However, she meets a woman who drops a blue ring as a result of a fortuitous encounter.