Haruka☆Ruka is a student at the prestigious Four Star Academy, where she is a member of the Wind Dance class. She has chin-length, sky blue hair styled into a messy bob with part of it tied up into two odango buns, and her eyes are a notable dual-color of pink and purple, often shown squinted when she becomes fired up.

In terms of personality, Haruka☆Ruka is quite excitable, bearing a similarity to the idol Yuzu Nikaido. Her primary talent lies in dance, and she is recognized as one of the top students in her class, having been selected for this distinction alongside other skilled idols like Laura Sakuraba, Ako Saotome, and Mahiru Kasumi.

Her role in the story begins with her introduction during a competition in the Summer Festival event, where she competes against Yuzu Nikaido as the first-place contender in the dance category. After being eliminated from the preliminaries, she receives a significant opportunity from Yuzu: the right to study dance in Los Angeles, confirming a period of study abroad. Following this, she reappears during a Christmas episode and later returns to LA, looking forward to the day she can defeat Yuzu. After a long absence from the narrative where her existence is not mentioned, she reappears along with other characters to compete in the selection for the next generation of S4, the top idol group at the academy. Ultimately, while she loses by a narrow margin in this competition, she is selected as the runner-up for the 27th S4 following Yuzu's graduation. A key relationship is her rivalry with and respect for Yuzu Nikaido, who serves as both a competitor and a motivator for her development. Her development arc sees her transform from a promising but defeated contestant into an idol who earns the right to study overseas and eventually returns to compete for a place among the academy's elite. Her notable abilities are centered on her strength as a dancer, which is her defining skill as an idol.