Kono Sekai wa Boku to Kimi wo Tsunagu

Synopsis

On the day of high school graduation, Haruki confessed his love to his childhood friend, Renta. However, on the way back, the two had an accident. Without warning, Renta appeared in front of Haruki as a spirit. "I'll always be by your side." I'll keep that promise... The day my favorite childhood friend became my lover. On that day, he became a ghost.