Worst KDRAMA You've Ever Watched?

Hyde, Jekyll and high dream

School 2013
Dream High 2
Pretty Man

Out of ones I've actually finished, Lie to Me. Just atrocious writing, I've no idea how I finished it. 

Also definitely A Gentleman's Dignity and Secret Garden. To the Beautiful You was pure fluff so it was an extremely easy watch, but it was pretty awful.

I dropped countless terrible shows over the years, too many to even list. But maybe the worst were things like Heirs, Hotel King and Time Slip Dr. Jin. I've no idea how they even got made.

Surplus Princess

Big man ( second leads was more interesting)
Heirs ( skip all of it, except Kim Woo Bin parts)
Blade Man 
Boysitter
Monstar
Pretty Boy
High school love on
Fall in love with me ( boring story, stale acting)

Five fingers
You who came for the stars
Big
Please don't hate me lol.

Vampire Prosecutor

To the beautiful you was so boring to me. It was kinda cute and funny, but I didn't find anything interesting other than those handsome boys. Also, the acting was meh and I think the "I'm-gonna-cut-my-hair-cause-then-I'll-look-like-a-boy-and-nobody-will-notice" it's just not for me.
My lovely girl was also boring to me. At least TTBY entertained me a little, but with this drama I couldn't even get to the fifth ep. I thought I was gonna like it just because Krystal and Rain but I didn't even like the argument and the love triangle made me nervous.
I also dropped High school love on (why did they choose a 14-year-old girl as the lead when there's lots of good grown actresses????? I mean she's a minor and the ten year old difference with the male lead was too much for me).