I regularly reread this, it's one of my favorite oneshots ever. There's so much that's conveyed purely through implication and metaphor, from the obvious (Kobayashi's issues with her father being the likely cause of her relations with men) to the more subtle (Kobayashi acting the way she does because she perceives Nakano as "mysterious" and thinks that is what Uchida is into). It's legitimately a masterpiece of complex character writing in a limited number of pages.
I understand why the open end upset people in this thread, but it's clearly a deliberate decision by the author. "Does sympathy lead to love?" is what Uchida asks Nakano, and the manga is explicitly leaving the answer up to the reader. (Although the fact that Nakano does end up falling for Kobayashi suggests to me what the manga's own answer is.)
