Don't know if the story's gonna end soon, but it looks like going forward it will develop pretty much as anyone expects it to, following all the sacred conventions of the rom-com genre.
Personally, I'd find it pretty funny if he rejected Tsuzuri then confessed to Nishino, just to get rejected, and turns out that she was never actually flirting with him, she was just being nice and friendly all along, and in fact she even has a boyfriend, so that both friendships end up awkward or worse. I'm sure no trauma will be stirred among readers...