Kano Yamanouchi is a former idol and a main character who operates under the anonymous online alias of JELEE, the masked singer and central figure of a musical group she forms. Before the events of the story, she performed as Nonoka Tachibana, the center of a popular idol group called the Sunflower Dolls, but was forced to leave after a scandal involving a physical altercation with a fellow member.

In stark contrast to her former appearance as an idol with black hair, Kano now has a vibrant blonde hairstyle and fair complexion. She has an older sister named Mion and a mother named Yukine Hayakawa, a music producer who managed the Sunflower Dolls; her parents are divorced. Kano is a bold, confident, and determined individual who is very straightforward in pursuing her desires and holds strong opinions that are not easily swayed by others. She can also be impulsive, reckless, and prone to acting without fully thinking things through, leading her friends to question her judgment when she proposes unrealistic schedules or tries to learn complex skills like songwriting overnight. Despite this, her energy is described as infectious, and she possesses a strong optimistic streak.

Her primary motivation shifts over the course of the story. Initially, she is driven by a desire to prove her worth and make a comeback after being discarded from her former group, largely to gain the approval of her mother. However, her experiences lead her to a more personal and authentic search for her own path, wanting to find what truly matters to her beyond the expectations of the entertainment industry. Her role in the narrative is as the catalyst and leader of the anonymous group JELEE, bringing together individuals with different talents: Mahiru Kouzuki, whose jellyfish mural she deeply admires, serves as the artist; Kiui, an introverted V-tuber, handles video editing and animation; and Kimura, a musical prodigy and former fan, composes the music.

Kano shares a particularly deep bond with Mahiru, as she finds genuine inspiration in Mahiru's art, which helped change her values, while she herself encourages Mahiru to overcome her self-doubt and embrace her creativity. This relationship is complicated when Kano, while trying to fight against her manipulative mother, realizes she has imitated the same behavior by potentially using Mahiru for her own goals, leading to a significant rift that challenges Kano's self-perception and nearly causes the disbandment of JELEE. Her other key relationship is with the composer Kimura, a long-time admirer who deeply idolizes her and who plays a crucial role in pulling Kano out of despair after her falling out with Mahiru.

Throughout the story, Kano undergoes notable development as she confronts her past, her failings, and her fears. She moves from a place of emptiness and a feeling of having nothing but her career, to a person who finds value in friendship and genuine creative collaboration. A significant part of her growth involves acknowledging that her past as an idol is still a part of who she is and recognizing that her previous work touched many people, even if she wishes to move beyond it. Her journey is one of learning to find self-worth not just in the acceptance of others or in proving herself to her mother, but in her own identity as an artist. Regarding her abilities, Kano is the lead vocalist and lyricist for JELEE, using her singing talent to express the group's emotions and ideas, though she does not possess the technical skill for music composition and must learn it.