Gabriel MILLER

Although he deserved to be in Hell for killing Alicia and so many other innocent people, him getting dragged to Hell was the most terrifying thing in the whole franchise.

How this guy doesn't even break into the top #200 of the most hated character is beyond me. 

Perfect chance for a ginger character and they blew it. This guy doesn't have a soul.

This guy is the definition of a moustache curling cartoon villain... Seriously, this character has some fanfiction tier writing.

He has absolutely no logical motivation, no dark past to lean on, absolutely nothing to justify why he is like this, he is just "pure evil" and its honestly quite dumb. In fact, he is so evil that his eyes turn evil and gives off an evil aura irl, because this is apparently a sunday morning cartoon. Oh and lets not forget the sexual harassment, cause we can't have an SAO villain who doesn't attempt to struggle snuggle a heroine, to get a cheap reaction out of the viewer... 

But dumbest thing about this character is the fact that he "sees the emotions of people as a color", so he kills people to see the apparently most beautiful color, "fear", lol, because of course it is. Seriously, was this character written by some kid going through prepuberty? This writing has "Shut up mom! You' don't understand!" written all over it... 

Because all normal children ask if you were to kill someone would you see their soul. Totally normal