Had I rated before the tenth episode, it would have been a 5, maybe 6. The acting above all felt shallow and lame. The male lead, whose character is supposed to live in hell, perpetually torn between his human heart and his vampire instinct, could not convey those affects. Gwi was so handsome I wanted to die (or get bitten), but his face was still, expressionless, a pity. He could, should, have been sexier, naughtier, mightier. The staging didn't help either. It felt fake and cheap. In a vampire story everything else has to look real so we can believe that vampires exist, at least whilst watching.
Then came the tenth episode. For some reason, almost everything improved. Or I just got used to it? Anyhow, I started to really enjoy the show. There was a scene (can't remember the episode) with a young girl hurrying over to help the fallen scholar. Tears gushed out. After that, I got seriously hooked. It was like a spell, with the beautiful song "Love You Again" highlighting" the romance.
The ending was moving too. I like that Gwi, even though he didn't have a human heart, knew what it meant to be a decent human. And I felt for him. Basically, he is the main reason why I managed to bear until episode 10.
So, if you can see this as a fairytale and not pour too much expectations in it, you may like it, even love it.