「It's just, on that day, something in us derailed――」 To determine the「honesty of the heart」simply from hearing the voice, that is the special ability of a girl―Yomibayashi Iwo. Unable to trust anyone, the lonely Iwo chooses to abort her life, yet when she next awakens, she stands at the platform of a station that doesn't exist―Kisaragi Station. Getting on the Spirit Train, Iwo was instructed by the Conductor to, together with Kuchinashi Chihiro and Shinomezaki Azuma who are in a similar situation, defeat the monsters that have strayed into our world.