Tooru's jealousy over Run isn't a plot device, it's the entire engine of the show, and the comedy lands because you can feel how real that panic is underneath every bit of slapstick. Run collects girls like they're Pokemon, completely oblivious to the actual chaos she creates, and watching Tooru orchestrate damage control while pretending she doesn't care is its own kind of love confession. The four of them don't resolve into a neat dynamic until you've watched them fail at it a dozen times first. It's a show about girls who genuinely like each other but can't stop hurting each other's feelings by accident.
Tooru and Run have been inseparable since childhood, so when they both end up at the same high school, Tooru expects their friendship to continue exactly as it always has. That fantasy crumbles the moment she witnesses Run flirting shamelessly with Yuko, another first-year student. What should have been a happy reunion instead becomes a daily exercise in managing chaos as Tooru watches her best friend bounce between romantic interests with zero self-awareness. As the school year unfolds, their friend group expands to include Nagi, who quickly becomes trapped in the same orbit of Run's dramatic antics and infectious energy. Between Tooru playing reluctant bodyguard, Yuko navigating Run's affection, and Nagi trying to keep everyone grounded, these four navigate the petty conflicts and genuine moments that define early high school. The comedy comes from watching four girls with wildly different personalities collide constantly, each one convinced they're dealing with the most ridiculous person in the group. Spoiler: they all are.