Teika Ichijōji is a second-year singing student at Hoshinomori Magical Arts High School, recognized as the "King" for his exceptional voice and serving as chairman of the Hoshinomori Summer Festival committee. He stands 177 cm tall with black hair and red eyes. Born on September 17th, his zodiac sign is Virgo. His artistic magic manifests visually as rose-shaped diamonds, known as "sparkles" or "Light of Arte."

A member of the prestigious Ichijōji family, Teika feels significant pressure from his older brothers, Masana and Shinra, to uphold their artistic legacy and noble reputation. This expectation contributes to his initial stoic and results-oriented demeanor, presenting a cool, reserved façade that masks a passionate and caring nature. A childhood friendship with calligrapher Aoi Suminomiya has evolved into a competitive rivalry for the top artistic position at school. Masana Ichijōji previously participated in the school's Art Session alongside Sakura Aigasaki, Kohana's mother, reflecting a centuries-old rivalry between their families.

Upon Kohana Aigasaki's transfer to Hoshigei High, Teika immediately declares her his rival due to their families' history. He expresses this antagonism through blunt criticism of her initial inability to produce artistic sparkles and reluctance to collaborate on festival preparations. His perspective shifts when Kohana demonstrates genuine admiration for his singing and creates her first sparkles while offering him a heartfelt bouquet of flowers. Teika gradually develops romantic feelings, especially after she affirms her appreciation for his artistry. By the festival's climax, he permits her exclusive use of his first name, acknowledging their changed relationship. He actively shields her from his brothers' interference, demonstrating protective instincts and a willingness to defy familial expectations.

Teika experiences a crisis when familial pressures temporarily strip him of his singing ability. Kohana's unwavering support and Aoi's unexpected intervention—disrupting a critical performance with calligraphy to reignite Teika's inspiration—help him recover his artistic expression. This incident catalyzes a reconciliation between Teika and Aoi, mending their friendship. Later, during preparations for a collaborative ensemble performance, Teika acknowledges the purity of Kohana's artistic intentions. Though initially citing their families' rivalry as a barrier, he agrees to partner with her, recognizing their potential to succeed together. His participation in a committee training camp suggested to foster unity indicates his growing openness to shared experiences and collaborative creativity.