Muku Sakisaka, a teenage actor in Mankai Company's Summer Troupe, possesses fluffy pink hair and light blue eyes with an average-height frame. He favors homely or childlike outfits like a white-and-teal sweater, light blue ripped jeans, and brown leather boots. Kind and modest by nature, he adheres to a self-imposed rule of performing one good deed daily. He idolizes shoujo manga princes, treating their stories as life guides to embody chivalrous ideals, which fuels his supportive disposition toward others. However, he battles severe self-doubt and a persecution complex, misinterpreting neutral comments as criticism and spiraling into negative self-talk. His hyperactive imagination transforms ordinary events—such as spotting a snail—into elaborate dramatic fantasies involving romance or peril.

Previously the track and field ace at St. Flora Middle School, Muku pursued athletics to emulate a manga protagonist rather than personal passion. A career-ending injury led him to audition for acting as an alternate path. Though initially struggling with confidence and line delivery, he perseveres by studying roles through manga analysis and observing fellow actors.

Within Mankai, he shares Room 202 with Kazunari Miyoshi, who cherishes his cuteness and exchanges manga insights with him. He reveres Tenma Sumeragi as a princely mentor and admires Yuki Rurikawa’s strength, having attended their same school and class. Misumi Ikaruga bonds with him over shared whimsy, especially triangle-themed activities. His cousin Kumon Hyodo is a beloved figure Muku describes as caring and radiant.

Muku demonstrates growth from early fluster at praise and fear of failure toward proactive initiative—researching roles via specialized manga (e.g., ninja stories for a play) and seeking advice from seniors like Homare Arisugawa and Chikage Utsuki. His dedication secures him the lead in "The Floral Prince," where he merges shoujo-inspired idealism with cultivated skill.

He routinely invokes shoujo tropes in daily life, dramatically pledging protection to the director during forest walks or recreating greenhouse scenes from gymnasium manga with Homare. These instances highlight his earnest enthusiasm and reliance on fiction for personal growth and role preparation.

Academically adept and popular at school—receiving abundant Valentine’s chocolates—he remains humble. Family influences his interests; his sister’s gymnastics passion inspires his manga selections. Grateful for his troupe’s encouragement, he strives relentlessly to become "a man fitting for the Director."