Yue, a princess from Ryuuto, leads the unit supernova at Flora Girls' Academy. Supernova holds the school's highest Noire rank, contrasting sharply with lower-ranked units like LiGHTs. She possesses long black hair often styled with two knots at the back and stands 164 cm tall, maintaining an elegant presence typically accentuated by her uniform and black mary jane shoes.

Her personality is stoic, aloof, and direct with strangers, projecting calm composure. This demeanor shifts noticeably around Tiara, toward whom Yue exhibits consistent hostility and emotional volatility, openly demeaning her. This animosity relates to Tiara's connection with Eliza, Yue's former mentor and leader of the legendary unit Ray. Despite her reserve, Yue demonstrates kindness toward animals, particularly through her hobby of collecting panda merchandise, contrasting her deep-seated dislike of magical beasts stemming from traumatic attacks on Ryuuto that caused significant civilian and military casualties.

Yue possesses exceptional musical abilities, including perfect pitch and a singing voice acclaimed as "The Successor of the Songstress," placing her among the academy's elite performers. She is also skilled in kenpo, indicating combat proficiency. However, she struggles with songwriting despite her vocal prowess and choir membership. Her closest relationships are with her supernova unit members, Millefeuille and Fiona, who serve as both friends and rivals in their shared pursuit of becoming top witches.

Her background includes apprenticeship under Eliza, creating a complex dynamic with Eliza's sister Tiara. The unit supernova functions as a foil to LiGHTs, showcasing top-tier academic and performance skills against LiGHTs' struggles, emphasizing the competitive tension between the units and their leaders.