Hideo Ōminato is a meticulous second-year student at Shiro High School and a dedicated member of its rhythmic gymnastics team. Hailing from Aoyama in Aomori Prefecture, his father operates an osteopathic clinic back home that treats the team members. His meticulous nature demands precise execution in all things, extending even to his cooking. He possesses mid-length steel blue hair with bangs covering his forehead, dark blue eyes, and distinctive thick-framed red glasses. For practice, he wears a plain white t-shirt and dark purple shorts, often seen with his team tracksuit unzipped over a lilac sports hoodie. A devoted fan of the local idol group "Aomori Nebuta Dream," he shares a lighthearted rivalry with Nagayoshi Onagawa from Ao High School over their idol preferences.