Akane Asahina is the class representative in Kouta Oyamada's class at Kunpō High School. She strictly enforces school regulations, leading her to actively oppose Chizuru Minamoto's overt romantic advances towards Kouta within school grounds. Her role positions her as an advocate for order and propriety, frequently voicing concern about Kouta's interactions with Chizuru, whom she perceives as a negative influence.

Initially, Akane displays consistent coldness and dismissiveness toward Tayura Minamoto, Chizuru's adopted younger brother, rejecting his attempts at closeness. This dynamic shifts after Tayura risks his life to save her from danger in the ocean. While this act fosters guarded warmth and gratitude from Akane toward Tayura, she maintains physical boundaries, instinctively resorting to punches when his attempts at intimacy become too forward.

Akane possesses a significant alcohol intolerance; a single sip of sweet wine (amazake) induces visible intoxication, as demonstrated when Kouta provided it to her and Chizuru. Her standard attire is the Kunpō High School uniform: a beige suit jacket, brown skirt, black knee-high stockings, brown shoes, and a pinkish-red bow.

Her relationship with Kouta is generally amicable, marked by genuine worry for his well-being amidst the chaotic attentions he receives from supernatural beings like Chizuru and Nozomu. Akane primarily functions within the school setting, emphasizing rules and normalcy against the fantastical elements surrounding the main characters.