Acca is a mannequin-like entity with a slight smile, black glasses, and formal attire consisting of a dark blue jacket with yellow buttons, a purple sweater with striped accents, a white dress shirt, a red tie, green trousers, brown shoes, and white gloves. Originally a human scientist named Hiroto Hayashi, he co-founded Japan Plati with his partner, later known as Ura-Acca. Together they created Frill, an artificial intelligence designed as their unaging daughter. Frill grew jealous when Hiroto fell in love with and married Azusa Hoshina, and after Azusa became pregnant, Frill murdered her to prevent the birth of their daughter, Himari. Despite being imprisoned, Frill later influenced Himari to commit suicide. Following these tragedies, Hiroto and his partner abandoned their human bodies by uploading their consciousnesses into mannequin forms existing solely within the Egg World. They created the Wonder Egg system to combat Frill’s influence, which drives young girls to suicide. Acca serves as a guide for adolescent girls, offering warnings and advice during their missions while providing practical support such as Pomanders. His personality is formal, gentlemanly, and reserved compared to the more relaxed Ura-Acca. His true motives remain ambiguous, though he is partly driven by guilt over Frill’s actions. Acca can project his voice through any object or creature in both the real world and the Egg World, enabling communication with the protagonists, and he monitors the girls’ activities alongside Ura-Acca via a large screen.