Tadayuki Isa/Biography

A Geography teacher at Shin Kawahama First High School. Tadayuki has one class where he teaches Naoto Kurogane, Haruka Hayami, and Shinnosuke Fukuda. At some point, he was transformed into an Apostle by Spinner Superior, and found Kana Kirishima exiting an adult store in a back alley. He took photos of the girl exiting and used it to blackmail her into sexual acts, of which he filmed, stopping Kana from escaping his grasp.

Bloodedge Experience - Part 1
In October, Tadayuki taught one of his lessons to Naoto, Haruka, and Shinnosuke, but quickly lost his temper at the first boy, shouting at him for his behavior and for not paying any attention. He went home early that night. The teacher spent some time off school, leaving his students to self-study.

Several nights later, Tadayuki called for Kana and she arrived at his apartment. As they begun to delve into their usual acts, the teacher started asking about Haruka, but was met with dismay by Kana, who asked him not to think about her. The teacher's apartment had fallen apart at the seams to the point where it was easy for Raquel Alucard to deduce his condition.

The teacher entered the Student Council room after school had ended and found Haruka. He set up a camera on the nearby table as the girl attempted to escape. Tadayuki lunged at her, getting the girl on the floor and begun to strip her against her will. Naoto burst through the door and punched his teacher as hard as he possibly could. The two began to fight as Raquel arrived and put Haruka aside on a nearby bench. Tadayuki lost his patience and began to transform further, large beetle legs erupting from his back. Tired of seeing his student run circles around him, Tadayuki set his sights on Haruka and Raquel, lunging towards them with his new legs. Naoto took the brunt of the attack and activated his Drive - Bloodedge.

Using Bloodedge, Naoto cut off Tadayuki's beetle legs and defeated the teacher, knocking him unconscious. He was later taken in by the Mitsurugi Agency and they performed a life-saving operation on him, removing the insect that had infected his body. The Agency kept the films he had made of himself and Kana, and also erased his memories of his life as an Apostle. Tadayuki took a temporary retirement from his life as a teacher.