Yamibo Darkness, The Hat, and Travelers of the Books contains episodes 1-13 of the anime directed by Yuji Yamaguchi of Studio Deen.

The sweeping, romantic cosmic saga of a girl named Hazuki, a high school student who has a serious crush on her older adopted sister Hatsumi. On Hatsumi’s 16th birthday, she is suddenly engulfed by a green glow and vanishes! Hazuki manages to follow Hatsumi to a mysterious place called “The Great Library”, curated by Lilith, that houses a fantastic labyrinth of books, each containing its own exotic fantasy world and characters. When Hatsumi vanishes into one of the books, Hazuki’s epic extradimensional search begins.