After the TV-series of Kimagure Orange Road, Kyosuke and Madoka have finally arrived at the point where they are close to graduation and have to decide where they want to go to college. Naturally, they want to go together, so beside all the studying they also have to look for a proper college where they can enter both. Hikaru, still a year from graduating, wants to support Kyosuke as well and does that in her own way. But while she does that, Madoka feels jealous and tells her feelings to Kyosuke. And then Kyosuke has to take action to finally decide on the girl he loves... thus concluding the story of the Kimagure Orange Road.

Ten years after the Holy War in Hong Kong, Mochizuki Jirou, aka the Silver Blade, and the lone hero who fought and defeated the Kowloon Children despite the loss of his lover, returns to Japan with his young brother, Mochizuki Kotarou. The two quickly discover that the Kowloon Children who survived the Holy War are seeking to infiltrate the "Special Zone", a thriving city protected by an invisible barrier that will not allow Kowloon Children entrance, unless they're invited. Red Bloods refers to the humans; Black Bloods are the vampires, and the Mochizuki Brothers are Old Blood, the last descendants of an elite clan of vampires. When Kotarou is abducted by one of the Kowloon Children, Jirou has no choice but to fight once more.

Demonic activity worldwide has significantly increased due to the involvement and corrupt practices of the Illuminati. To combat the unnatural influx of demons, the Vatican Headquarters decides to hold the annual Exorcist Certification Exam early and allow for as many exorcists as possible to take up the mantle. Straight from the Vatican, one of the most powerful exorcists, Lewin "Lightning" Light, arrives at True Cross Academy to help prepare the students for the exam. The ease and mastery with which Lewin performs exorcisms quickly impresses Ryuuji "Bon" Suguro, who has lost his ambition to continue his studies, and Lewin surprisingly accepts him as his apprentice. Amid the worsening situation, twin brothers Rin and Yukio Okumura are sent to locate the recently missing exorcist Shura Kirigakure, who seems to be chained to a decades-long contract with a powerful, immortal demon hiding in Aomori Prefecture's dangerous, snowy mountains.