Ginko is on another adventure as he is brought to a very peculiar island, by a young boy Nagi. Ginko is taken to see a girl, who the island inhabitants refer to as "Ikigami" and is said to be able to perform miracles however Ginko discovers that there is more to this.

On a rainy day Ginko takes a rest from his travels and comes across a man named Kourou who seems to be obsessed with a rainbow. To pass the time Kourou reminisces in his past, with the events which led to him pursuing rainbows whenever they appear. Ginko explains to him that the rainbow which he is searching for is actually a Mushi known as "Koda" but there seems to be more to it.

It is spring, and Ginko is taking a boat through a river, when the boat's boy, Kaji, asks Ginko whether he could help his mother, who's forgetting things and can't sleep. At first glance it may appear to be progressive amnesia, however something isn't right.

Ginko arrives at a secluded place, to meet an old acquaintance, who seems to be in charge of a large volume of archival, confidential text. Ginko is allowed to read it, and discovers it is the work of Tan'yu, a writer. Tan'yu is the descendant of the Karibusa family, being born with a black mark on a part of their body.

A lady named Aki discovered a green stain on her wedding gown, one year later she gave birth to a boy who, now grown up, has the same marks on his body. It turns out that the boy was originally born not as a human but as some shapeless green blob, which then turned into a human. Her husband asks for Ginko's help yet he is unable to save her son because it's the work of a "Watahaki".

In a cold mountainous region, Ginko is wandering around the snow cover plain when he hears a sound ringing through the cold air and he also notices some rust on a tree. Ginko enters a nearby town to find the rust covering everywhere, including the people. The village chief tells Ginko that this is a sickness that has been affecting the town for 14 years that the people have been slowly losing the movements of the limbs and it's said that a girl called Shige is the cause of it.

Taku is a peculiar young boy who has always wondered who the people were that always passed by the mountains during the rainy seasons. One day he meets a boy named Isaza, while catching fish. It seems that not only Taku can see the Komiyaku in the mountains however Isaza seems to know a lot more about the mountain than him.

"The world is filled with life unknown to man..."