One-Eyed Fish (Episode 12)

One-Eyed Fish is the twelfth episode of the anime series. This episode is effectively Ginko's origin story.

Synopsis
Ginko's origin and the cause of his becoming a Mushi Master is shown.

Plot
A Mushi Master named Nui comes across an injured boy in the forest and takes him in. That night, the boy named Yoki recalls how he and his mother were lost crossing the mountainside when they were caught in a mudslide. Yoki wakes up after the mudslide covered in mud and debris. His leg is injured and beside him is the body of his mother, who had been killed by the mudslide.

Nui finds the boy collapsed from exhaustion in the forest, and takes him in.

Initially she is reserved towards Yoki, telling him he can stay until he heals and then must leave. But over time Nui warms to Yoki, discovering that the boy has a natural ability to see Mushi, a strong curiosity for the subject, and that he has no family now that his mother is gone.

Yoki finds white, one-eyed fish in a pond near Nui's house. When Yoki asks what happened to the fishes' eyes, Nui explains that the Mushi in the pond, feed on other Mushi, generating a silver light. Repeated exposure to this light caused the fish to turn white and lose one eye. This light was also the cause of Nui's white hair and missing eye. Nui says she doesn't know the name of the Mushi which cause the light, but she calls them "Ginko".

Yoki worries that further exposure to this light will make Nui lose her remaining eye, but she re-assures him, saying that there are no fish with two missing eyes. Yoki eventually realizes that when the Tokoyami eventually consume the fishes' remaining eye, the fish effectively disappears- a fate we see Nui succumb to, as well.

Nui also explains that she has spent the last six years in the mountains, looking for her husband and son, who she initially feared had their memories eaten by the Tokoyami. She tells Yoki that, if you fall prey to the Tokoyami, you must keep one eye tightly closed to protect it, and cling to some specific memory, to avoid having your memories taken by the Tokoyami.

After Nui turns into Tokoyami and Yoki manages to escape from it, he wanders confused and exhausted in the forest. His hair is now white, his left eye missing and his remaining eye green, and his memories are gone, except for the word "Ginko", which he adopts as his name. He worries that his empty eye socket is attracting "strange creatures", which he takes as a sign that bad luck will follow him where ever he goes.