I don't think any of these are really bitches :/

Let's just quote Brooke:
'How about trying to steal my cheerleading squad ? Or entering me in Rogue Vogue just so she could screw me over ? Or her midnight round of strip basketball with MY boyfriend ? Or humiliating me in front of all our friends last weekend ? You know stop me any time cause I can go on and on !'

By far! She is the only woman ever on this show that I never sympathized with(even for a split-second) or liked.She was just a nasty,bitter bitchy woman who really got on my nerves.Good props to the actress who played Nikki because she played a bitch well! All of those woman listed have acted bitchy at least one point during this series but I would never consider any of them to be the biggest bitch in OTH.

And Nikki

I thought she had redeemed herself in season 4 but no she had to come back in season 7 at her worst!