The Sound You Heard Sometime
Itsuka Kiita Oto (いつか聴いた音)
Based on information from Kumagami, the student council members camp out in the mountains to find another ability wielder.
In an alternate world, a small percentage of children are able to manifest superpowers upon reaching puberty. Yuu Otosaka, a boy who awakens the ability to temporarily possess others, hopes to use his power to live an easy going high school life. However, he is caught red-handed by the mysterious Nao Tomori and is forced to transfer to Hoshinoumi Academy, where he and the other student council members must help students who have trouble controlling their abilities.
An original story from Jun Maeda, creator of Angel Beats and Clannad, Charlotte explores the supernatural lives of these teenagers and the price they must pay for being special.
(Sources: IMDb, MAL Rewrite)