At 22 years old, when the series begins, Hina is trapped in a toxic dynamic with Shū. For Hina, this was not just an affair; it was a reenactment of her high school emotional attachment. However, as an adult, the romance had soured. Hina was described as a "damaged woman going through a painful relationship with a married man," one in which she was "suffering and had no control". The relationship placed her in a position of constant submission, where she was forced to accept being "the other woman".

However, it was not until the 1990s that hina relationships became a staple of shoujo manga. Series like "Sailor Moon" (Bishoujo Senshi Sailor Moon) and "Cardcaptor Sakura" popularized the trope, featuring male protagonists who were often depicted as being oblivious to the affections of their female classmates. These storylines typically followed a predictable pattern: the hina would develop feelings for her senpai, who would eventually come to realize his own emotions and confess his love.

Hina characters often slot into the mature, responsible, secretly fragile archetype. In Domestic Girlfriend , Hina Tachibana is the older sister, the teacher, the “adult” – which makes her romance with Natsuo immediately taboo. But the real genius of her storyline isn’t the scandal; it’s the emotional labor.

Ultimately, romantic storylines involving Hina are never just about finding a partner. They serve as a mirror to her internal evolution, transforming her from a isolated individual into a deeply connected protagonist. Overcoming Emotional Isolation

: Hodaka chooses Hina over the safety of Tokyo, rescuing her from the sky and asserting that love outweighs societal obligations. Narrative Theme

Thus began a love story built on the rubble of an affair, turning a student-teacher relationship into a full-blown, secret romantic affair.