I wasn't so sure about this manga when I saw it, but wanting to know what is popular in the Asian countries, I gave it a try. I didn't regret it!

First, the story. I got so much into it, the ups and downs - it's like an emotional roller-coaster. There are some little flaws though, as at some point I thought that some bits seemed illogical in the story but the whole main plot from a to z worked.
It has some under-themes going on as well, like bullying, appearances in the society, the money, and more which on the top of my head I can't remember.

Then the art, I think it was good as it was clear and the boys were fashionable!

For characters, I think Tsukushi is a strong female character and is brave to go through all these troubles and I don't know how she fell in love with Tsukasa, but I think the mangaka took strongly the side of "you never know when love will hit you" which adds to the tragic side of the story.
There are strong females characters in the story which I like to see, Shizuka, Tsukasa's sister, Shigeru, the old maid, which all are willing to help Tsukushi because of how she is.
As for the boys, despite that the main ones are good looking and fashionable, they are mostly seen as very rich boys - we see only two major developments with Tsukasa and Rui.

I really enjoyed this manga even if it was long. I felt annoyed, I cried, I laughed, I was caught in the story.

Overall, I think it's a good romantic/dramatic story if you are into this genre, then go for it!