"Love Live! Nijigasaki High School Idol Club" centers on the activities of the Nijigasaki High School Idol Club, a group of students who come together to create and perform as school idols. Unlike traditional idol groups, the club operates on a more individualistic approach, allowing each member to shine in their unique way while still collaborating as a team. The story begins with Yu Takasaki, a second-year student who revives the school idol club after it was disbanded. Inspired by her childhood friend Ayumu Uehara, who aspires to become a school idol, Yu takes on the role of the club’s producer and manager, supporting the members in their endeavors.

The narrative explores the personal journeys of each idol as they balance their dreams with the challenges of school life. Ayumu Uehara, a kind and determined girl, serves as the emotional core of the group, often encouraging others to pursue their passions. Kasumi Nakasu, a vibrant and confident performer, brings energy and creativity to the club, while Setsuna Yuki, a former student council president, secretly pursues her idol dreams under the pseudonym "Nana Nakagawa." Other members include Emma Verde, a transfer student from Switzerland; Kanata Konoe, a laid-back and sleepy girl with a hidden talent; Ai Miyashita, a tech-savvy idol who uses social media to connect with fans; Rina Tennoji, who hides her expressions behind a digital board; Shizuku Osaka, a reserved and bookish girl who discovers her love for performing; and Karin Asaka, a model with a strong sense of individuality.

The series emphasizes the growth of each character as they overcome personal insecurities, build friendships, and strive to create memorable performances. The club faces various challenges, such as organizing events, gaining recognition, and competing in idol festivals. The narrative highlights themes of self-discovery, teamwork, and perseverance, as the idols learn to support one another while pursuing their individual goals. The story culminates in their participation in the Love Live! competition, where they aim to showcase their talents and leave a lasting impact on the school idol community. Throughout the series, the focus remains on the characters’ development and their shared passion for bringing joy to others through their performances.