Unaired TV episode bundled with the light novel's volume eight.

After an embarrassing high school class reunion with their successful classmates, who have proper jobs, relationships, and even children, the Matsuno sextuplets return home to sulk about their status as NEETs. They spend the night drinking away their sorrows, eventually falling unconscious, until they awaken in a strange world of memories, centered around one of the brothers' biggest high school regret. As the sextuplets navigate this memory world, they encounter their embarrassing past selves from high school, as well as those of their friends. All the while, they try to uncover whose regret was great enough to trap them in this strange world, so that they can make their way back to reality. However, they're running out of time; this world of memories is unstable, and the sextuplets may lose their chance to make things right if they're too slow....

Three hundred years ago, a genetic experiment gone wrong caused the mutation of all forests on Earth. Armed with consciousness, the vegetation sought to destroy all of humankind, and the war that ensued turned the planet into a hellish dystopia. In the present day, Agito, a young boy, lives with his father in Neutral City—a village maintaining an uneasy truce with the neighboring forest. One day, Agito, on his way to collect water, becomes separated from his friend and stumbles upon a relic of the past: a girl sleeping in a mysterious machine. Agito awakens the girl, Toola Cm Sacl, and introduces her to the village. But outside forces have ulterior motives for the girl, who holds the key to restore the Earth. Misguided by Shunack, a soldier from the old world hellbent on destroying the forest, Toola follows him despite Agito's warning. Determined to save Toola and unify humankind with the forest, Agito borrows the power of the forest and pursues her.

Ebichu the hamster seems like the perfect house pet: she cleans, shops, cooks, does laundry, and anything to please her master, known only as Office Lady (OL). Unfortunately, OL and her unfaithful boyfriend, combined with Ebichu's uncontrollable exuberance and love for ice cream, often earn her severe and bloody punishment. However, Ebichu doesn't seem to mind the abuse if she achieves her goal of making her beloved master a little bit happier. (Source: IMDB)