The first-generation Skyline (SI/S2 model) was manufactured by Fuji Seimitsu Kogyo (later Prince Motors) in 1957. Although the Skyline was not originally a Nissan model, the name survived the merger of Prince Motors and Nissan Motors in 1966, and it has become an important car in Nissan's history, loved by many fans. In the long history of the Skyline, the 10th generation Skyline (R34 model) is one of the models that has been enthusiastically supported by fans. Available as either a 4-door sedan or a 2-door coupe, the 10th generation Skyline was developed with the aim of further improving its renowned athletic performance by shortening the wheelbase by 55 mm from that of its predecessor, the 9th generation Skyline (R33). Development by Nissan's engineering team was thorough. The rigidity of the body was drastically increased to improve driving performance, and the 10th generation Skyline clearly outperformed its rivals with its strong body and excellent driving performance. However, the 10th generation Skyline faced an uphill battle in terms of sales. While its predecessor, the 9th generation Skyline (R33), achieved total sales of 217,133 units, including the Skyline GT-R, the 10th generation Skyline sold 64,623 units, less than one-third the number of its predecessor, and a significant drop in sales volume. This had a profound impact on the Skyline's future. Nissan decided to discontinue development of a successor to the R34 Skyline, and instead decided to sell the large Infiniti-brand sedan in Japan as the 11th-generation Skyline (V35), which was to be sold under a completely different name from the Skyline. With this change, the iconic inline 6-cylinder engine was replaced by a V6 engine, and the wheelbase was significantly extended, resulting in a drastic change in the Skyline's character. Therefore, the 10th generation Skyline is still loved by many fans as the "last Skyline" that carries on the tradition of the first generation.

The story is set in Tokyo, where an old school right in between the neighborhoods of Akihabara, Kanda and Jinbocho is in danger of consolidation and closure. Nine girls, centering Honoka Kosaka, have stepped up to defy the imminent danger facing their school. “If we want to protect our beloved school, we need to do what we can? we need to become idols!” Hoping against hope there’s something they can do about this, the girls strive to become famous, spread the word about their school, attract more students, and save the day. Now their “School Idol Project” begins to make their dreams come true! “Make our dreams come true!”

A third-year student at Otonokizaka Academy. She is the student body president of Otonokizaka Academy and a dance coach for μ's. She was raised in Russia, the home of ballet, where she received a gifted education in ballet from an early age, and although she had great hopes for her future as a ballerina, she failed in her career. Her dancing ability is at a professional level. At first, Eri was skeptical of Honoka Kousaka's plan to increase the number of applicants to Otonokizaka Gakuin and prevent the consolidation of Otonokizaka Gakuin through publicity for the school idol program, but Honoka's enthusiasm inspired her to join μ's herself. Her grandmother is Russian, and she is fluent in Russian. Her habit is to say "Harasho" in Russian.