Psyren

Ageha Yoshina finds a mysterious red phone card marked "Psyren," then discovers that his classmate Sakurako Amamiya carries the same kind of card shortly before she vanishes. Searching for her drives him to call the number printed on it, where a series of questions leads him into a place unlike the world he knows. There, a survival game pits its participants against monsters called Taboo, while Ageha and Sakurako awaken psychic abilities known as PSI. Returning home is possible, but each journey into Psyren reveals that the missing people are far from the only thing they should fear.