Shiori Kirino, nicknamed "Shiitan," serves as a main character and talented idol in the music group SOL 4. Her rebellious nature leads her to frequently disregard rules and operate by her own methods. Despite this, she exhibits strong loyalty to her friends and consistently offers support when needed. Music defines her core passion, especially singing and dancing, and she dedicates significant time to refining these skills. Her energetic performances captivate audiences.

Initially perceived as a troublemaker, Shiori reveals an underlying kindness and caring personality. Her commitment to fellow SOL 4 members and willingness to assist others drive her popularity among peers and fans. She confronts challenges including rivalries with other idol groups and internal conflicts within SOL 4, yet maintains unwavering determination to achieve the group's success. Her journey highlights growth through perseverance, collaboration, and pursuing personal aspirations.

Shiori's dedication and musical talent ultimately elevate her to prominence in the idol industry. Her infectious energy and performance skills attract a large, devoted fanbase, solidifying her status among the most popular figures in the field.