Muku Sakisaka is a member of the Summer Troupe at the MANKAI Company. He is a kind-hearted and modest young man whose personal motto is to perform one good deed each day. He treats shoujo manga as his bible and deeply admires the princes depicted in those stories, aspiring to become a princely man himself. Despite his gentle and reserved nature, he is easily flustered and suffers from a severe persecution complex, often interpreting ordinary comments as criticism and spiraling into anxious thoughts about his own inadequacy. When left alone, he can act recklessly due to his overactive imagination. Before joining the theater company, Muku was the ace of his school's track and field club, and he retains notable physical strength that sometimes surprises his fellow troupe members. He is a student at St. Flora Middle School and later St. Flora High School, and he lives with his parents and older sister. Muku shares a dormitory room with Kazunari Miyoshi. He is deeply supportive of his cousins, Juza and Kumon Hyodo, and holds a positive view of others even while he struggles with self-doubt. Over time, through the encouragement of his family, friends, and fellow actors, he gradually gains confidence in his acting abilities. He is known for his hyperactive imagination, which leads him to envision elaborate scenarios inspired by the smallest everyday occurrences. His growth as an actor is marked by his determination to study reference material and learn from his troupe mates, and he eventually takes on leading roles such as Florence in The Floral Prince. He also owns a teddy bear named William. Despite his soft-spoken demeanor, he has a strong sweet tooth and holds the record for the fastest fifty-meter dash among the company members.