Nishiki feels trapped by her family who already have entire future planned down to how many babies she'll have. So it's no wonder when she meets Atsumori, she clings to the first chance she's found to escape, through his proposal to essentially elope with him to Tokyo. Two years pass before she manages to make it there to take him up on his offer, but then she discovers that he wasn't actually serious about any of it. But too late now, because she's been nursing this crush for years, and she's not about to give up.
In general, I'd call this manga a pretty
decent shoujo. That is, both art and writing are of a reasonably good quality for the story they're trying to tell, but at the same time the concept itself isn't all that interesting. I think it's unlikely any reading it will be really drawn in as you get for the truly great shoujo manga. The main reason to read this really is if you like male tsunderes, because that's pretty much Atsumori to a tee.
The one major complaint about this manga that I have is that it makes the same mistake I've seen so many shoujo stumble into, which is in the first chapter or so, the manga characterizes the protagonist as having some other interest other than boys, which immediately falls by the wayside as her entire motivation becomes chasing after a boy. In this case, the first chapter claims Nishiki is so into studying that she seems completely uninterested in boys. By chapter two, pretty much her entire goal is now is to persue Atsumori and any concerns about studying are entirely secondary. It really weakens her character, and is surely frustrating to a great many readers who do like romance, but not as their single goal in life.