Mr. Murohashi is a physical education teacher at the elementary school attended by the main character, Hiyori. He is a tall, muscular man with a strong build, and his most distinctive physical trait is his long, catfish-like beard, which he takes pride in. Despite his intimidating appearance, he is a kind and supportive figure who encourages his students to do their best. He has a great fondness for protein supplements and is highly skilled in sports, particularly the hammer throw, an ability modeled after the real-life Olympic athlete Koji Murofushi. In the series, Murohashi acts as a coach and mentor, especially to the energetic boy Masao, whom he trains in one episode to help him become stronger. His role is largely comedic but also highlights the value of discipline and encouragement. He appears as a recurring adult character who interacts with the children in school settings, offering guidance through his rigorous but good-natured training methods.