Munou na Nana

Anime adaptation of the manga Talentless by Iori Furuya and Loose Boy.

At a school built on a remote island in the middle of the ocean... Young people gifted with superpowers, known as the Prodigies, undergo intensive training designed to help them confront a terrible threat called "the enemies of humanity." A new student arrives among them, Nana, claiming to be able to read people's thoughts. One day, she receives a text message: to save millions of lives, she must assassinate one of her classmates... Could a formidable superhero murderer be hiding behind this seemingly inoffensive girl?