Okay, I liked this drama. I honestly did. It's not exactly different from other dramas, it doesn't really bring anything new, but it's enjoyable and just overall a nice watch. However, there was one thing which was constantly grating on my nerves, and that was the character of Na Doo Rim. She was fine in the first half, relatable, kinda quirky, all that cliched stuff that you'd expect. I honestly liked the way the relationship developed in the beginning, and even though it's pretty by the mold and cookie cutter, I wasn't mad at it. However...what infuriated me was the way she acted after they had "broken up". It was the typical "I like you but I have to pretent I don't because we can't be together" which always, always gets on my nerves, but honestly, what was keeping her from simply being honest with him, and maybe apologizing? She didn't apologize to him, not even once, for what she did, and instead was at times really nasty to him, for no reason whatsoever. It is probably the way her character needed to behave so that the drama and the tension would last longer, but that doesn't mean it wasn't annoying. Also, it's not like Kang Ju is blameless in this - he keeps basically stalking her and annoying her and is being really petty and childish. I get it, you're hurt, but please, do try to keep some of your dignity.
In the end, the reason why she left was just complete bogus. Again, the drama simply needed to be longer, so they had her leave for stupid, dumb, very dumb reasons. And the way she did it, too. Just infuriated me. And can we talk about how she literally kept his son from him for, like, several YEARS? I mean, if he hadn't looked for her, he would never get to know his own son, or even realize he existed. When he finally found her, her grandmother was like, thank you for finding Doo Rim, and I was like, shouldn't she have gone to HIM? Because unlike him, she knew where he'd been all this time, and was content to just stare longingly at the sky, because....why? WHY CAN'T YOU BE TOGETHER AT THIS POINT? YOU CAN!!!! THERE IS NOTHING AND NOBODY IN YOUR WAY!!!! NA DOO RIM! WHAT THE FRICK!?