Arisa Ichigaya is a third-year student at Hanasakigawa Girls' High School, where she serves as student council vice president. She plays keyboard for the band Poppin'Party. Her family runs the pawnshop Ryuuseidou, a traditional building with a basement that the band uses for practice. It was in this shop that Kasumi Toyama discovered the Random Star guitar. Arisa lives with her grandmother, and they seldom celebrate Christmas together.

As a child, Arisa learned piano at a music school alongside Tae Hanazono and Rei Wakana, but she quit due to waning motivation and the demands of middle school entrance exams. She later resumed playing to join Poppin'Party after Kasumi inspired her. Before that, Arisa was reclusive and spent most of her time at home helping in the pawnshop, leading to rumors at school that she was a ghost. Despite claiming laziness, she achieves excellent grades.

Arisa has long, slightly curled blonde hair typically styled in two pigtails secured with ribbons or bands. Her bangs spread across her forehead with a few curled strands sticking upward, and her forelocks are pinned back with cross-shaped clips. She has gentle light brown eyes. Her fashion favors mature, feminine styles with lace or floral details and long skirts. Her height is 152 centimeters.

Personality-wise, Arisa is introverted, moody, and sharp-tongued, frequently arguing especially with Kasumi. She struggles to express her genuine feelings and becomes easily flustered or blushes when complimented. Beneath a cynical exterior, she is deeply caring, though she often denies feelings of loneliness or jealousy. Her hobbies include tending to bonsai trees, which she names and speaks to daily, and browsing the internet. She dislikes leeks but enjoys anmitsu, brown rice, and hard-boiled eggs. She tends to overpack for trips and always carries a favorite fluffy towel. Through her involvement with Poppin'Party and student council duties, she gradually opens up and values friendship more, while maintaining her blunt communication style.