Awayuki Reizei attends Seio Girls' Academy as a classmate of Kayleigh Glanzelius. She possesses blonde hair, blue eyes, stands 165 cm tall, and was born on December 12 with blood type B. Academically, she neglects her studies, preferring instead to immerse herself in reading books, even during test periods. Her personality is reserved, and she is a nature lover.

Her parents are masters of flower arrangement, belonging to the same school as Utano Sasou's parents. This family connection leads Awayuki to join the academy's flower arrangement club. Within the club, she develops a fierce sense of rivalry with the exceptionally skilled Chihaya Kisakinomiya. She is never content with his abilities and consistently measures herself against him as a competitor.

Utano Sasou is her closest friend. Privately, they use nicknames: Utano calls her "Yuki-chan," while she addresses Utano as "Ucha-chan." However, in public settings, she formally addresses Utano as "Gozen," reflecting an awareness of Utano's popularity and social dynamics.

While primarily focused on surpassing Chihaya's talents in flower arrangement, Awayuki occasionally demonstrates limited empathy toward him. Her club activities, academic tendencies, and reserved nature define much of her role within the school environment.