Description
Sayo Hikawa serves as the guitarist for the band Roselia and is the older twin sister of Hina Hikawa. From childhood, Hina consistently outperformed Sayo in every activity, mastering new skills effortlessly while Sayo required extensive study before practice. This dynamic fostered Sayo's profound inferiority complex. She chose the guitar specifically because it was an activity Hina did not pursue.

Sayo exhibits a serious, meticulous, and somewhat cold personality, rejecting mediocrity or carelessness while maintaining high standards for herself and others. She speaks formally, typically addressing people by their last names, though she makes exceptions for her sister and Tomoe Udagawa, whom she calls "Tomoe-san". Despite her stern exterior, she denies certain preferences, like an affinity for fluffy animals or french fries. She harbors a strong dislike for carrots, originating from childhood when she ate Hina's carrots to help her, only to be scolded for not eating her own—an exact reason she later forgot.

Initially close, Sayo's feelings of inadequacy caused her to distance herself from Hina, eventually attempting to exclude her entirely. Gradually, however, Sayo works to repair their relationship, demonstrating increased kindness toward Hina and others. This shift appears in her menu dialogue, where she nearly refers to Hina as someone she treasures before hesitating, contrasting earlier bitter remarks. Her development includes becoming more approachable, such as offering guitar lessons to Touko Kirigaya despite initial doubts about her teaching ability. She also indulges more in leisure activities, a change from her past insistence on constant band practice.

Physically, Sayo possesses slanted green eyes and long, light teal hair reaching her navel, styled with forelocks behind her ears and a single loose lock framing her face. Standing 161 cm tall, she is the tallest member of Roselia. Her casual attire blends tomboyish and cute elements using pale and dark shades.

Beyond music, Sayo reads music magazines avidly, once carrying eight in her school bag. She practices archery and later developed interests in baking—often seeking guidance from Lisa Imai—and gaming, regularly playing the Tank class in Neo Fantasy Online. After high school, she enrolled at Keiho Women's University's Faculty of Law and pursued a driver's license.

A significant moment in her growth involved composing Roselia's song "39" (later retitled "Avant-garde HISTORY") after a 39°C fever from over-practicing. Inspired by Yukina Minato's perspective on their band's supporters, the song expressed gratitude, with the title "39" interpreted as "thank you" ("san-kyu").

Sayo appears in the chibi anime spin-off *BanG Dream! Girls Band Party! Pico*, including its seasons *Ohmori* and *Fever!*. She participated in collaboration events, featuring character designs based on Ram (*Re:Zero*) and Makima (*Chainsaw Man*).