Five years ago, something horrifying happened on Kamioki Island. Something so nightmarish that it stripped all memory from Mari Wakatake's mind even as it left every other human on the island dead in its wake! Now enrolled against her will at an isolated girl's academy, Mari is unaware that hidden eyes are watching her, waiting for her memory to return. Buried in her psyche is the most terrifying secret of all: while Mari was the only human who lived, she may not have been the only survivor! As something in a female skin invades Kaihou Academy, Mari's only hope may lie in a strange girl to whom she is inexplicably drawn yet cannot trust. (Source: Sentai Filmworks)

Hatsuki is a highschool student living with her sister, Hatsumi, who she has a huge crush on. On Hatsumi's 16th birthday, she is suddenly surrounded by a green light and disappears in front of Hatsuki. She manages to follow Hatsumi with the help of a being resembling a fat baby chick (literally), ending up in a place called The Great Library, which is full of different worlds stored in books. Hatsumi wasn't there, though, so the search for Hatsuki's great love begins and involves traveling from book to book. (Source: AniDB)

Upon waking up, Subaru Natsuki finds himself in a parallel reality of the fantasy world he has come to accept as his own. Despite being familiar faces, Subaru's friends are vastly different, especially as they enjoy the life of modern society that he knows all too well. This mysterious world captures the intrepid boy's interest nonetheless, and a clash between his antics and the dubious inhabitants soon leads to all sorts of amusing scenarios.

There is a new urban legend circulating Tokyo. It claims that if you make a request in the Ask-a-Thief Channel, the Phantom Thieves of Hearts will show up and bring justice by stealing a corrupt person's heart and making them regret all their wrongdoings. As strange and inexplicable events continue to happen all around town, more people submit their requests in hope that the mysterious vigilante group will help. Kazuya Makigami is a burglar by night, but has started to have second thoughts about his crimes and those who help him commit them. Unable to stand up to his comrades himself, Kazuya submits a request to the Ask-a-Thief Channel.