Azuki Shinatsu is a sophomore at Tenbi Academy and a supporting character. She serves in the Student Council Security Division and ranks among the school's most powerful Maken wielders as an A-Rank ability user. Specializing in kicking-based martial arts, her combat style emphasizes physical strikes over solely relying on her Maken.

Before the Clash with Venus arc, she actively sought to join the organization Kamigari after graduation to financially support her impoverished family; the status of this request remains unclear, likely impacted by hostilities between Tenbi Academy and Kamigari. She also works part-time at the maid café Macaron.

Physically, Azuki sports chin-length red hair, purple eyes, and typically wears purple fingerless gloves with a small bandage across her nose. Her outfits frequently sustain extensive damage during combat, degrading down to her underwear more consistently than other characters, regardless of opponent or battle circumstances.

Personality-wise, she projects a tough, tomboyish exterior but hides a softer, sentimental side, particularly a noted attraction to bears. She values combat integrity and reacts with irritation to rule violations, as demonstrated when Takeru Ooyama interfered in her duel against Kai Kurigasa. Though initially angered by his rule-breaking assistance, this encounter established their acquaintance.

Her narrative introduction occurs during a duel witnessed by Takeru, centered on winning a stuffed bear—a victory later revealed by her rival, Garrett Kinua, during a school induction ceremony. She also participated in the welcoming party for new students Takeru, Inaho Kushiya, and Kengo Usui, confirming her position within the Magical Enforcement Committee alongside Uruchi Minaya.