In August of 1995, Mikiya Kokutou meets a young kimono-clad woman named Shiki Ryougi. When he finds out that they go to the same school, he attempts to befriend her. Though her upbringing is unconventional and she herself is strange, Mikiya is not deterred, and Shiki gradually opens up to him. But Mikiya's life will be changed forever by this simple meeting, and in ways that he never imagined, as he begins to see a deadly side to his new friend...
The chronological order of the parts is: 2, 4, 3, 1, 5, 6, (Remix,) 7, Epilogue. Watch it in this order if you want to have an easier understanding of the story. Or just watch the Remix after Part 6.