TSUUGAKU DENSHA - KIMI TO BOKU NO HEYA

Tsuugaku Densha - Kimi to Boku no Heya summary:

From Night Constellations: Morishita Haruna is a high schooler who has a crush on a guy, called "Haru" (by his friends), whom she had always seen at the train she rides on. One day, when waking up Haruna was shocked to see "Haru" sleeping in her bed! Neither one of them had known why "Haru" was there. After introducing themselves to each other Haruna knew that "Haru" is actually his surname and his full name is Harukawa Kanata. Kanata was just about to leave, but an invisible wall on the door is preventing him from getting out of Haruna's room. Him being unable to leave, Haruna has no choice, but to go to school while Kanata stayed in her room. At the train station, an old man tried to molest Haruna, but Kanata saved her?! But this Kanata doesn't know Haruna!! Rushing back home, she saw the Kanata who slept in her room still being there! What happened to Kanata's body?