Ibuki Aihara discovers that the man she's in love with has a fiancée. Overwhelmed by shock, she attempts to jump off and kill herself, but by chance she encounters Hiroya Chigasaki, a boy who is in the same situation she is in. Finding out about their circumstances, Hiroya approaches Ibuki with a proposal: "Let's steal each other's love rivals". An unpredictable love suspense story unfolds on a heartbroken boy and girl! (Source: LINE manga)