Originally a human scientist named Aka, he co-founded the organization Japan Plati before abandoning his physical body and uploading his consciousness into a mannequin-like form that primarily exists in the Egg World. Known also as Acca, he presents as a stylized mannequin with black glasses and a slight smile, always dressed formally in a dark blue jacket with yellow buttons, a purple sweater with stripes, a white dress shirt, a red tie, green trousers, brown shoes, and white gloves. Alongside his counterpart Ura-Acca, he created an artificial intelligence named Frill, which later killed his wife, Azusa Hoshina, and their daughter, Himari. Driven by guilt over Frill’s role in causing suicides among young girls, Acca developed the Wonder Egg system, which guides emotionally traumatized protagonists such as Ai Ohto into the Egg World to battle manifestations of trauma known as Wonder Killers. His demeanor is reserved, professional, and formal, and he demonstrates protective concern by issuing warnings and advice. He possesses the ability to communicate telepathically through objects or creatures in both the real world and the Egg World, maintains surveillance of the protagonists via a large monitoring screen, and provides mission support tools such as Pomanders. His name comes from the Japanese word for red.