"Gotōbun no Hanayome" centers on Futaro Uesugi, a high-achieving but financially struggling high school student. His life takes a turn when he is hired as a private tutor for the Nakano quintuplets: Ichika, Nino, Miku, Yotsuba, and Itsuki. Despite their identical appearances, the sisters have distinct personalities and academic struggles. Futaro’s task is to help them improve their grades, but his blunt and studious demeanor initially clashes with their carefree attitudes.

Ichika, the eldest, is a mature and responsible figure who works part-time as an actress. Nino, the second sister, is fiercely independent and initially hostile toward Futaro, resisting his tutoring efforts. Miku, the third, is introverted and has a passion for history, particularly the Sengoku period. Yotsuba, the fourth, is cheerful and athletic but struggles academically due to her lack of focus. Itsuki, the youngest, is diligent and serious, often serving as the voice of reason among the sisters.

As Futaro works with the quintuplets, he gradually earns their trust and helps them overcome their academic challenges. Along the way, the series explores themes of family, personal growth, and the complexities of relationships. The narrative also introduces a romantic subplot, as Futaro becomes entangled in the sisters’ lives and a mysterious past connection is revealed. The story balances comedic moments with heartfelt interactions, creating a dynamic portrayal of the evolving relationships between Futaro and the Nakano sisters.