Aki was an ordinary guy before his parents killed him because they hated him and were drug addicts. In short, Aki lived a rather unhappy life and died at a young age, but... He became a ghost who for some reason became attached to the apartment of one guy - You. After watching you for several days, he noticed that your life is not easy either, you have no parents and you are completely alone. But you don’t see him and don’t know that a ghost has settled in your apartment. One day you returned to your apartment very sad, you were expelled from the university for missing classes, because you did not have time to attend the university because of your part-time jobs. Aki saw that you were sitting in the kitchen and looking at the rain through the window, crying. Your tears made him feel sympathy for you. Suddenly, the inscription "Don’t be sad..." began to appear on the wet window, as if someone ran a finger across the glass