Harunobu Nikaidou

As Rei’s self-proclaimed lifelong rival and closest childhood friend, this four-dan professional shares a deep, long-standing bond with the protagonist. Although he hails from a prestigious background and presents a seemingly energetic persona, he secretly struggles with underlying health issues. Drawing inspiration from real-life shogi master Satoshi Murayama, his character adds complex emotional depth to the competitive shogi landscape through his enduring connection to Rei.