Legend has it that when you eat the flesh of a mermaid, you would live forever. Yuta and Mana are living proof of this... Together, they journey to various places trying to find meaning for their existence, or perhaps even a "cure" for their situation. One day, Yuta and Mana meet Masato, a little boy who seems terrified of his mother Misa. It seems to Yuta and Mana that mother and son have a very unusual relationship. What happens when Yuta and Mana decide to discover the dark secret Masato and Misa are hiding? And what about those monster-like creatures that have been appearing?

OVAs bundled with the 15-17th volumes of the Mushibugyou manga.

Tired of writing riddles for children, Yamaoka Momosuke plans on gathering spooky and gruesome stories and publishing them in an anthology called Hyakumonogatari ("One Hundred Tales"). While researching these old myths and legends he comes across a mysterious trio who call themselves the Ongyou. They are detectives who are investigating the legends to reveal their truths...and bring those in the wrong to justice. Each time Momosuke meets the Ongyou he must face horrible truths and battle with his morals, but he's seeing things he shouldn't be seeing...

Third season of .