Hajimete Ageru!
What separates a good short story from a bad one when dealing with 30 pages or less is being able to generate an emotional reaction from the readers. This story didn't have that at all, and the times when it did try to show an emotional shift in the characters, the story was bogged down by the odd pacing and inconsistent dialogue. Also, I don't get the obsession with the whole "first boyfriend" thing. Did he say that when he confessed or something? It seemed like everyone's focus was on that but it didn't make any sense for the girls to claim that was the only reason he was dating her. I mean, he was at least a year older than her; you're telling me there were no girls in his grade who never dated before?
Kare Wa Tsumetai Furi O Shite