Considered a genius, high school student Fuutarou Uesugi excels at studying and obtains a perfect score on every test. Due to his intense focus in that regard, he is a reclusive person with no friends. Additionally, he lives in a tight financial state as a result of family debts.

Fuutarou's mundane lifestyle is interrupted when Itsuki Nakano, a new transfer student, contests him for his usual lunch seat. After a short altercation, Fuutarou emerges victorious by insulting Itsuki's eating habits, which angers her enough to leave. However, when Fuutarou learns that he has been offered the private tutor position of a wealthy family's academically hopeless daughters, he immediately regrets his prior encounter. It turns out that the beneficiaries of his tutoring are none other than Itsuki and her four identical siblings: the shy Miku, the cheerful Yotsuba, the devious Nino, and the mature Ichika!

Teaching these quintuplets may prove more difficult for Fuutarou than he initially expected, as the last thing they want to do is seriously study. Now, Fuutarou must face the various challenges of tutoring five beautiful yet eccentric girls.