The Kameido High School tennis club exists in name only. While its four members have access to rackets and a court, their time is almost entirely consumed by nonsensical antics that defy logic, physics, and common sense. The series follows the rapid-fire, chaotic daily lives of these girls, where a trip to a bakery can devolve into an impromptu wrestling match and a routine practice session might be interrupted by a spaceship refueling.

The group is anchored by Yuri Oshimoto, a sharp and athletic first-year who is the only member capable of actually playing tennis. She is perpetually exhausted by the behavior of her three upperclassmen, serving as the reluctant straight man who reacts with exasperation as reality unravels around her. Her primary tormentor is Kanae Shinjo, a hyperactive second-year whose boundless energy and eccentric impulses allow her to casually break the laws of physics by sinking into solid ground or splitting herself in two. The chaos is further enabled by Nasuno Takamiya, an incredibly wealthy and airheaded heiress who funds the groups outlandish schemes without ever grasping their impracticality. Rounding out the quartet is Marimo Bando, a tall, dim-witted second-year prone to bizarre misconceptions and shocking behavior, such as developing a taste for undergarments or attempting to kidnap children.

Set primarily within the grounds of Kameido High School, the narrative is strictly episodic, abandoning any pretense of a sports tournament arc or character development in favor of pure, absurdist comedy. Recurring motifs often involve the girls visiting Nasunos extravagant properties, encountering recurring side characters like the alien refugee Tomarin who becomes Marimos roommate, or dragging Yuris long-suffering younger brother Yota into their schemes as a makeshift butler.

The series is notable for its breakneck pacing, with episodes lasting only two minutes and packed with rapid dialogue and visual gags. Later narrative arcs do not deepen the plot but instead escalate the absurdity, introducing interdimensional travel and surreal illusions while maintaining the core formula of Yuri struggling to survive the cheerful insanity of her senpai. The story holds a Guinness World Record for the shortest animated television series, delivering a complete comedy experience in roughly the length of a commercial break.