Anju Yūki is a third-year student at UTX High School and a core member of the popular school idol group A-RISE, performing alongside Tsubasa Kira and Erena Todo. The group's significant popularity bolsters UTX High School's reputation and inspires other school idol groups. Anju maintains a characteristically calm, composed, and princess-like demeanor, complemented by a sweet voice. She exhibits minimal concern during competitions or when approached for autographs, including by rivals like Nico Yazawa and Hanayo Koizumi.

Physically, Anju has long, curly orange hair with straight bangs and distinctive lilac-colored eyes. She performs on several A-RISE songs, such as "Private Wars" and "Shocking Party".

Her interactions occur primarily during events involving the rival group μ's. A-RISE acknowledges μ's potential during the Love Live! preliminaries, offering encouragement and access to UTX's rooftop stage for their performance. Later, Anju and her groupmates witness μ's performances, including "START:DASH!!" and "Snow halation," reacting with respect and admiration. Following μ's victory in the preliminaries, Anju, Tsubasa, and Erena directly congratulate them.

After graduating from UTX, Anju stays connected to the school idol community. She participates in the large-scale school idol festival organized by μ's as their final project. During preparations, Anju collaborates closely with Kotori Minami on costume design, while her fellow A-RISE members assist with song composition and event coordination, signifying mutual respect. On the festival day, Anju joins the collective of school idols welcoming μ's to the stage, symbolizing unity within the movement.