The main female character, Tsubaki, is a strong female lead without being over-the-top aggressive or so in charge that it's unrealistic. She has a mind of her own and saves people from situations, but also gets saved herself, which I find a lot more realistic than other female leads who are either one or the other. I found her to be an extremely likable main character without her being too weepy or too tsundere.
The main male lead, Shin, I had to learn to like. At first I was a little thrown off by his situation (and one of the reasons I almost stopped reading) but after a few chapters I was extremely impressed: he was respectful, handsome as heck, funny, and unpredictable at times. His few spots of jealousy, when he's normally in control, also added elements of realism for me. He was neither too possessive, nor too passive towards his love. He was also willing to be tough on his romantic interest, and push them to be a better person, but was also surprisingly gentle at times.
There are some very nice romantic scenes, as well. ;)
The story itself carries a few surprises. The last volume was a whirlwind, but despite going in a surprising and different direction it didn't detract from the main story or the characters at all. I was pleasantly surprised!!
So, in summation: this is a good quality shoujo manga, with likable characters, beautiful and flawless art, with a healthy dose of romance and humor, and unpredictable story lines. I loved this manga, and feel it should be much more popular if more people give it a chance!
