Fullmetal Alchemist

Allen Walker is not your average fifteen-year-old boy - he is an exorcist and a member of the Black Order, an organization charged by the Church with the elimination of Akuma. The Akuma are the minions of The Millenium Earl - an evil demon-like entity intending to cleanse the world by destroying the entire human race in the manner of Noah's great flood. Allen and the other exorcists are special people who are compatible with a substance named Innocence, which allows them to form Anti-Akuma weapons; and as such Exorcists are the only ones capable of fighting the Akuma. Allen and his friends must battle to save humanity from the Akuma and Earl's evil plans.

One night Ageha Yoshina passes a public phone as it's ringing, but as he answers he finds that there's no one on the line and hangs up, retrieving a calling card bearing the name Psyren in the process. Thinking nothing more of it, he goes home. However, intrigued by the disappearance of his classmate Amamiya, who was also in possession of a Psyren card, Ageha begins to dig around. He soon learns of an urban legend about a secret organization that leads those sick of society to paradise, and the only way to contact them is with the calling card. Intent on saving Amamiya, Ageha uses the card on a public phone. Though, when it is discovered he has a Psyren card, Ageha is pursued; and as he tries to escape his cell phone begins to ring. Upon answering his phone, Ageha is transported to a strange new world where he must now learn how to survive if he has any hope of getting home or finding out the truth behind the mysterious Psyren.