Neko ni Hakuchou, Hotaru ni Koban

Art teacher Hase Hotaru is confounded by one of her students, Nekome Yuna. Yuna fell in love at first sight with Shiratori Ako, a part-time teacher at the same school, and she is aggressive in her pursuit. However, Ako has quirks of her own, and her true feelings are inscrutable. The story of a student's unrequited love and the unexpected effects on the adults around her.

(Source: Kadokawa, translated)