Hanabi Yasuraoka and Mugi Awaya appear to be a picture-perfect couple to those around them. Yet, their hidden anguish lies in unrequited love for others. Hanabi harbors deep feelings for her childhood friend, Narumi Kanai, now her homeroom teacher, only to watch him become entangled with the alluring music teacher, Akane Minagawa. Meanwhile, Mugi carries a long-standing affection for Akane, stemming from their past connection during his middle school days. When fate brings Hanabi and Mugi together, they form a pact to fill the void left by their unattainable loves, seeking solace in a physical relationship that masks their emotional emptiness.