Individual parts of human emotion often take the shape of flowers known as "Fragments," and those with enough Fragments may become "Reflectors," creatures that wear specialized rings that allow them to link their thoughts, memories, and emotions to people whose sentiments waver. There are two kinds of Reflectors: those who wear blue rings to safeguard individuals on the verge of depravity by conserving their Fragments, and those who wear red rings to avoid unpleasant feelings by snatching the Fragments of those who are on the verge of great misery. Despite her desire to interact with others around her, transfer student Ruka Hanari's shy and introverted demeanor usually comes in her way. However, she occurs to run into a woman who drops a blue ring as a result of a chance meeting.