
I feel like Lee Bin's personality shift was too drastic. Not going to say I don't like him but I thought it was too extreme too fast from the type we see at the beginning.

Actually if you look at it closely, he has always been polite to everyone that talked to him. The only time he's being a jerk is when he first met Hwagok and he's too hungry to care etc and him being a jerk afterwards might probably be because he's emotionally constipated after so many years of being alone, and found a plaything. Once he realized he love Hwagok, he mellowed down to how he supposed to be given the chance that he could stop being alone...
There are a few scenes that's weird even for me, I agree, but overall, he's just a lonely guy that found love (๑•ㅂ•)و✧

Basically the end killed the story for me, aside from the predictability of it. They go on to say what Subaru does with his life but nothing about her. She's supposed to be a hard working girl who wants to be stronger so what did she do with her life after graduation? If you're going to try to build a strong female lead, you'd think the author would show the protagonist's achievements. I did like the side story in the middle--flipping the script on the douche bag.
1st I'm one of those who didn't like the ending. That being said the new work doesn't interest me if it's going to be King Xun x Zi