Let me begin with one thing, this drama isn't the best drama you'll watch, but it's not necessarily the worst one either.

The story is mediocre, with multiple cliches but for some reason, I couldn't personally stop watching it. It does have unexpected twists and turns, and the overall concept of the story is a fresher image to vampirism that I've seen presented in dramas. The acting is minimal, some parts showing amazing acting while others reveal this lack of good acting you'd expect in a way. It's more of a drama where you have to see past the faults of the story, casting, and other variables to enjoy. I mainly continued watching just to finish and end the story that I had begun watching. If you're up to see why this drama is so bad and so good (?) at the same time, I would recommend it. It's an odd thing to enjoy almost, where you know some parts you don't like, such as the acting, yet it's got that drama appeal where you wanna continue watching. Again, Blood isn't the BEST drama I've watched, but I've honestly seen worst.

Side Note: The main female lead will make you want to punch yourself in the face every now and then with her acting, but the eye candy of the main and second male leads will help you overcome the urges to stop watching in my honest opinion.