Endora at least never tried to murder Darrin. When Samantha’s father Maurice found out she’d married a mortal, he obliterated Darrin, literally erasing him from existence. Only Samantha’s absolute insistence forced Maurice to bring Darrin back, and he very nearly couldn’t do it.
FWIW, Samantha marrying a mortal was in her parents’ eyes akin to a princess royal marrying and living in the bush with a Tasmanian aborigine.
Not “despicable,” he falls under the “too perfect to like” category.
How about Lumpy from Leave it to Beaver? He started off being a bully and then just changed into a harmless sort of douche.
Understandable – witches in the Bewitched universe are not merely folk-magicians or neopagans, they are (like genies in I Dream of Jeannie, or the Q in Star Trek) a nonhuman supernatural race, for all intents and purposes gods, with nearly-unlimited reality-altering powers, and not “mortals.”
They’re also pretty close to descriptions of The Fair Folk.
Claire Underwood (House of Cards) just turns my stomach.
I always felt sorry for Wil Wheaton. If someone had offered me a part as a regular character on a Star Trek show when I was a teener, you wouldn’t have been able to keep me away. I would have found it kind of upsetting when all of fandom started to hate me. Even if I could totally understand why they hated me. Fortunately, Wheaton seems to have bounced back pretty well.
That being said, I never understood why the Robinson family didn’t feed Dr. Zachary Smith to the monster of the week somewhere by the end of the first season.
True, but He didn’t get blown up with a grenade by his squad mate, he didn’t have to take the rap like the most trustworthy member of the team and spend who knows how long in prison where they don’t take kindly to dirty cops, and he didn’t kill his wife and child before committing suicide with their bodies. He engineered a way to keep himself out of prison and would likely find some way to get by in the world.
I guess I must watch the wrong sortt of TV, because I don’t know most of these characters, so I’ll just note that King Friday XIII is kind of a self-absorbed and tryannical despot.
Archie Bunker from All In The Family. Probably the biggest bigot in tv history.
Yes, but he was a loveable bigot! 
I nominate the entire cast of Friends, except maybe Phoebe. A close second is that horrible brat Megan from Drake and Josh.
No, right show but wrong character. If you want to say she’s nasty because she’s a defense lawyer, well, you could fill this whole thread with lawyer characters.
No, the really despicable character from Hill Street Blues was Police Chief Fletcher Daniels (and he appeared in 71 of the 144 episodes so he can be considered a major character.) Actor Jon Cypher really knows how to play a smarmy, unrepentant jerk. Daniels was an a-hole in his first appearance and remained one all the way to the end.
Nobody deserved comeuppance more than Cersei Lannister. The White Walkers are going to overrun Westeros, and by now (mostly because of her) I’m kind of rooting for them.
Helga from Hey Arnold
Angelica from Rugrats
The Gromble from Ahh! Real Monsters
Plankton from Spongebob Squarepants
Mandark from Dexter’s Laboratory
I’m guessing we don’t have many Desperate Housewives fans here, because no one nominated Gabrielle Solis, who has (as far as I could tell) no redeeming qualities whatsoever.
Pretty much every character on Curb Your Enthusiasm. In every situation, every character is completely unreasonable and makes everything a disaster.
Mike/Meathead on “All In The Family”
Archie is a legitmate hero–he dropped out of high school to take care of his mother/siblings. He fought in WWII and while he’s a bigot, he can learn better. There was a gay character early on who Archie got used to, he liked the son from the Jeffersons (Lionel?) and so on. Yeah, he uses “un-PC” words but he’s a product of his times and can learn better.
And then there’s Meathead. A filthy hippie who won’t get a job, who refuses to obey house rules, mooches food, sits in Archie’s chair, fights with Archie over the TV and constantly belittles and insults Archie.
And eventually, the character runs off with some other woman, abandoning Archie’s daughter and his son.
Part of the reason Archie doesn’t seem so bad is that despite being a bigot, Archie has redeeming qualities–he’s brave, loyal, supports a family…etc. Meathead has no good qualities at all, whatsoever.
Most. Vile. Character. Ever.