Ikuyo Kita is a sixteen-year-old first-year student at Shuka High School who serves as the lead vocalist and rhythm guitarist for the band Kessoku Band. She is a girl of average height with a slender build, red hair that she styles into loose curls, and yellow eyes. Despite her cheerful and extroverted appearance, she is noted to be rather flat-chested.

Her personality is overwhelmingly bright, energetic, and sociable. As a self-described social butterfly, she loves interacting with people and maintains a wide circle of friends, often finding herself at the center of conversations. She is kind and attentive, but her straightforward and overly honest nature can sometimes be unintentionally cruel or insensitive, especially toward more introverted individuals like her bandmate Hitori Gotoh. Because of this, band leader Nijika Ijichi has playfully called her a natural sadist. Kita is also highly active on social media, where she posts photos and manages the band's online presence. She has a deep, almost obsessive admiration for bassist Ryo Yamada, having been inspired to join the band after seeing her perform on the street. Her only notable point of insecurity is her given name, Ikuyo, which she hates for sounding old-fashioned and embarrassing, and she strongly prefers to be called by her surname, Kita.

Kita initially joined Kessoku Band under false pretenses, claiming she could play the guitar despite having zero experience. Overwhelmed by the pressure and guilt of her lie, she fled from the band right before its first live performance. After her departure, guitarist Hitori Gotoh was recruited to fill the vacancy. Later, Kita encountered Hitori at school and, impressed by her guitar playing, asked for lessons. This led to an unexpected reunion with the other band members, where she tearfully confessed her deception. Noticing calluses on her fingers that proved she had been trying to learn on her own, Hitori encouraged her to rejoin the band, and she was formally welcomed back.

Kita's role in the story is that of the charismatic frontwoman. She is the band's primary vocalist and, despite her late start, its rhythm guitarist. Her outgoing nature and large social media following make her the natural choice to handle public relations and promotional duties for the group. Her motivations are rooted in a sense of mediocrity; she views her own life as ordinary and envies people like Ryo who seem to walk an extraordinary path. Being in the band gives her a chance to prove her own worth and to support her talented bandmates, particularly Hitori, whose musical potential she deeply respects.

Her relationships with the other members of Kessoku Band are central to her development. She holds an intense, rose-colored admiration for Ryo, often interpreting everything the stoic bassist does in the most positive light. Her connection with Hitori is one of contrasts and mutual respect, as her extroverted energy both overwhelms and encourages the anxious guitarist. She also shares a close, sisterly bond with drummer Nijika, who often acts as the voice of reason to balance Kita's enthusiasm.

Throughout the series, Kita undergoes significant development as a musician. Starting from absolute zero, she practices relentlessly under Hitori's tutelage. In just a few months, she progresses to the point where she can perform live competently. A key moment of growth occurs during the school festival concert, when Hitori's guitar string breaks during a solo. Without missing a beat, Kita performs an impromptu guitar ad-lib to cover for her, buying valuable time and showcasing her newfound confidence and skill. This event also marks a turning point in her relationship with Hitori, as she begins calling her by the more affectionate name Hitori-chan. Beyond her musical abilities, Kita is athletic, often asked to substitute for other school sports clubs, and initially a good student, though her grades begin to suffer as she dedicates more time to band activities.