Hikawa-sensei wa Otaku Kareshi ga Hoshii.

A high school student with a quiet interest in otaku culture meets a girl who shares his hobbies and enjoys spending time with him, including cooking and other shared activities. They grow close during spring break and begin a relationship. When school resumes, he discovers she is now his homeroom teacher, known for being strict and unyielding. This revelation causes shock among students and staff. The story follows their relationship, which becomes complicated by the teacher-student boundary.