Worst Characters:
Simmons
He's a creepy fuck who couldn't handle being rejected by Ada so he rewrites his top researchers DNA to make her look like Ada, kicking off RE 6's plot. By the end he's spouting gibberish about "protecting the country" and being even more of a creepy fuck with Ada. Worst villain in the franchise and a poor follow up to Albert Wesker from RE 5.
Carla Radames
She actually could have been a sympathetic villain had the writing been better. Forced to be an experiment for her own research, her identity taken by her boss, starting to lose her own sense of identity. Tone down some of her evil antics and you could actually feel for the character. Instead, she goes on a tirade and tries to destroy the entire world and create "a new one" like every other RE villain. By the end she's every bit as one dimensional as Simmons.
Jessica Sherewat
She spends most of her screen time getting super jealous of Jill. And by jealous I mean, like, super fucking spiteful. She also complains constantly. It isn't until they get to the ship that she talks about anything but Jill or complaining. The entire time she can't take the hint that Chris ain't got time for her shit.
Jessica: "So, Jill, Was it?"
Chris: "Was what? Stay Focused!"
Jessica: "She was your partner from before, right?"
Chris: "Yeah, my partner. From before. What about it?"
Jessica: "I WAS, you know, JUST ASKING!"
You know what? I'm just going to say most of the Revelations cast:
Bunch of forgettable nobodies.