Nemuri no Fuchi

A girl disappeared during a game of hide-and-seek in the forest eight years ago. Since then, labyrinths have appeared in various locations, leading to more disappearances. Kaori vanished after playing hide-and-seek with Shuhei and was never found. Shuhei has carried guilt over her disappearance and wishes to be drawn into the labyrinths to search for her. He discovers an entrance to one of these labyrinths and enters to uncover the truth behind the phenomenon.