Raised by Father Fujimoto, a famous exorcist, Rin Okumura never knew his real father. One day a fateful argument with Father Fujimoto forces Rin to face a terrible truth--the blood of the demon lord Satan runs in Rin's veins! Rin swears to defeat Satan, but doing that means entering the mysterious True Cross Academy and becoming an exorcist himself.

The surge of demonic activity around the world has the Knights of the True Cross worried at the highest levels. An important meeting at the Vatican will have serious effects on the lives of Rin and his Exwire friends. Back at True Cross Academy, the students get a sense that something is brewing with the arrival of an unexpected and definitely unconventional new instructor! Meanwhile, Yukio struggles to understand the strange fire in his eyes, a fire he has kept secret from everyone. Can he confront the flames inside him alone, or will they consume him?