A cat-like alien from a distant galaxy, MuuMuu, arrives on Earth. His goal is to learn about home appliance technology on Earth to recover the technology his species has lost. The protagonist, Sakurako, has a typical university life, but everything changes with MuuMuu's arrival! What begins as an unexpected cohabitation quickly turns into a whirlwind of chaotic events. The chemistry between Sakurako and MuuMuu leads to a super-spectacular, appliance-filled, and cat comedy adventure.

During recess, Olivia, a foreign transfer student who doesn't know English, plays a game of "look-the-other-way" with Hanako Honda, a loud-mouthed airhead. Their rowdy behavior spurs the ire of Kasumi Nomura, a deadpan loner constantly teased by her older sister for her tendency to lose games. Not willing to compete, Kasumi declines Olivia's offer to join the fun, but eventually gets involved anyway and dispenses her own brand of mischief. Soon, a strange friendship blossoms between the peculiar trio, and they decide to form the "Pastime Club," where they are free to resume their daily hijinks. Whether it be failing to learn English, trying desperately to become popular, or getting caught by teachers at the wrong time, school life will never be boring when the girls of Asobi Asobase are up to their hilarious antics.

High schooler Ganta Nakami has trouble falling asleep most nights. As a result, he is irritable at school, always searching for an opportunity to find a secluded place to doze off. On the other hand, Isaki Magari is a free spirit who is well liked by her friends, but no one is aware of her sleep disorder. She makes use of the school's abandoned astronomy club observatory as her secret sleeping bunker when she needs to get some shut-eye. As fate would have it, Nakami finds Magari napping in the observatory. When Magari discovers that she and Nakami have something in common, she offers to share her secret sleeping spot with her fellow insomniac. As the two find warmth in each other's company, the struggles they face start to become easier to confront.

University is back in session for Iori, and so are the booze-fueled parties! Between diving club shenanigans, a surprise from his sister, and wild tests of courage, normal college life is anything but. Dive back into the madness with Iori and his beloved crew of lively splash artists.