Shuuichi Seno

A long-time childhood companion of Tsumugi, this classmate of Shintarou shares a deep, enduring bond with her that has spanned many years. Having attended the same academic institutions throughout their lives, he remains a constant presence in her journey. His shared history and lifelong connection to Tsumugi make him a pivotal figure in her social circle, maintaining a steady friendship that has survived every school transition.