Summary by cleofe maliga
Assiah is the human world and coexisting with it is Gehenna, the demon realm. Although it is impossible to make any kind of contact between the two worlds, the demon have found a way and that is to possess anything that exist in the Assiah. Satan, the Demon God, wants to enter Assiah but he doesn't have anything to possess because his enormous amount of powers cannot be contained in a weak being. So he created Rin, his son from a human woman and have him live in Assiah so that he can possess him in the future. As a human, Rin has abnormal strength and endurance and along with his twin brother Yukio they both were raised by Fujimoto Shiro, an exorcist. When Fujimoto dies, Rin decides to become an exorcist as well and enrolls at True Cross Academy where his brother is already an exorcist too. Together, they trained in order to exterminate the Demon God, Satan.
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