Warning: Major spoilers for Emi’s route contained below.
While rather short and simple, Emi’s route definitely has a lot of heart. While its length could be seen as a drawback, it also means a smoother, tighter sense of pacing: gone are the meandering hi-jinks and grating comedic moments, instead focusing on well-executed moments of sweetness and adorable bonding with Emi, which then transitions into revealing some of her deep-rooted issues. And although they were fairly obvious from the beginning, it did not lack emotional impact in the slightest.
Emi, seemingly the typical genki-girl type, uses her devotion to athleticism both as an outlet for her frustrations, and as a way to distract herself from her neglected feelings of loss. As a child, she had lost two very important things in her life: her father, whom she saw as a model for healthy behavior and as a symbol of encouragement, and her legs: the essential parts of herself needed in order to move forward, both physically and emotionally. That was why she had been so determined to improve so quickly, in order to move away from her past.
However, despite her physical recovery, her emotional damage was still raw and untended to. She was happy to be near others, attracting people with her irresistible cheer, but all her relationships were superficial and hollow. Even Rin, her friend, knew nothing about her trust difficulties. And because of the distance she put between them, she ended up sabotaging all of her relationships herself. She tried her hardest to remain in denial about her loneliness, reasoning that it would be better to be unloved, than to be loved and hurt once again.
She also displayed an extreme sense of pride, and not simply in her abilities on the track. The mere implication that she is anything but healthy and normal, that anything about her life would need improvement or change, would send the good-natured Emi into a fierce rage, even if such advice was purely well-meaning. She loathed pity above all else, hating the idea of needing to be saved. To her, it would mean that she has been incapable of accomplishing anything herself, despite her best efforts to adjust.
When Hisao managed to bridge the gap, after all her failed attempts to keep their relationship surface-level, Emi still has to take things slowly, gradually revealing more and more difficult things about her past. These conversational “warm-ups” were very touching, culminating in a relationship that she can at last feel secure in, looking forward to the future without being weighed down by the past.