The characters receive an email from Ovan requesting them to go to Δ Hidden Forbidden Festival where a mysterious summer festival is set up. There they encounter an AIDA Chim Chim who wishes to peacefully co-exist with the players of The World. It then transforms into the word "Returner", which Haseo assumes it to mean that Ovan will return to The World.
Himari’s 16th birthday will be one she never forgets. Unexpectedly, she receives a will detailing her inheritance of a mysterious estate: the Momochi House. She arrives only to discover that the home was built on the cusp between the human world and the spiritual realm. There, she encounters Yukari, Ise, and a peculiar boy named Aoi, who seems to be concealing a shadowy secret.
Mitsuki loves singing, but a malignant tumor in her throat has prevented her from pursuing her passion. However, Mitsuki's life turns around when two fun-loving Shinigami appear to grant her a temporary reprieve from her illness--and give her singing career a magical jump-start.
