The girl Kotonoha Katsura (voiced by Okajima Tae) who was on the same train with him made Ito Makoto (voiced by Hirakawa Daisuke) unable to forget her for a long time. The seemingly distant distance between the two was slowly shortened by the day-to-day train life. There is a legend among teenagers that if you set the photo of the person you like as the background of your mobile phone and it is not discovered for 3 weeks, you can realize your wish to become a lover. Although Makoto does not believe it, he still does it to express his feelings for Kotonoha. Makoto's deskmate Saionji Sekai (voiced by Kawaharaki Shiho) discovered Makoto's secret, and she enthusiastically decided to help Makoto achieve his wish. But in the process, Saionji Sekai found that her feelings for Makoto had changed subtly. Looking at Makoto who was only paying attention to Kotonoha, Saionji Sekai's mood was very complicated. Makoto finally confessed his feelings to Kotonoha, and the two agreed to meet at the station. However, Makoto, who came to the station with joy, found that it was Saionji Sekai who was waiting for him. Cheng, who is naturally indecisive, is unable to properly handle the complex relationship between these three people. A series of irresponsible and wrong choices pushes Cheng into an irreparable tragedy.