The triplets subvert every expectation you have about them in the same breath they establish it. Each sister is a different flavor of chaos, sadistic, perverted, dangerously strong, and the show never settles into a rhythm where you can predict the punchline. The comedy comes from watching three fundamentally broken kids absolutely dismantle their exhausted teacher, one escalation at a time, and realizing the quiet one is somehow the scariest of all.
Three sisters. One classroom. Absolute chaos. Mitsuba, Futaba, and Hitoha are eleven-year-old triplets, and they share almost nothing except a last name and a talent for making life difficult. Mitsuba's got a sadistic streak and talks like she's already in high school. Futaba combines athletic prowess with a perverted sense of humor and honestly frightening strength. Hitoha looks quiet and sweet until she opens her mouth, revealing she's potentially the worst of all three. Their new teacher, Yabe Satoshi, walks into class expecting a normal year. He leaves every day questioning his life choices. Between getting physically destroyed, psychologically tormented, and roped into increasingly bizarre schemes, Yabe's main crime is existing in the same room as the triplets. Add the school nurse Kuriyama Aiko into the equation, and suddenly the girls decide their life project is forcing these two adults together, consequences be damned. Mitsudomoe is pure elementary school mayhem played completely straight. No character is safe, no situation too strange, and mercy doesn't exist in this classroom.