I don't understand why everyone's freaking out over this one. It's a really great concept and, like one person said, it addresses an idea that's fairly common, and experience that's (honestly) almost universal, but is almost never talked about. In just ten pages, this story zeroes in, starting from page one, on this idea and does not let go.
It doesn't feel tragic to me 'cause no one dies like in Philosophia (I'll never recover from that thing) and there's no connection. The story is entirely about MC. her love interest isn't even a love interest, or a character, until the last page. Ogawa's first appearance is a head with "OGAWA" written across the face in lieu of facial features. Ogawa isn't a person, she's a concept. She's unrequited, unexpected love, and that's all she's meant to represent.
Personally, the emotions I felt were directed at MC, not at Ogawa or even a presumed, potential relationship. Because it's not real. What's real is the feelings MC has. Deserving of the Aaaaangst tag, not Tragedy or WTF am I reading? I think the story does exactly what it intended to do and it's impressive that it managed to do so in so few pages. The mangaka clearly knows what they're doing. I enjoyed it, but I don't really feel sad. Feel sad for what? If anything, this is a moment for growth for the MC. But we never got to know Ogawa. I don't care. I just think it's an interesting story with a likable MC who is easy to empathize with. I wish her happiness in the future.