I think the question of whether Kitten is a plant (whether or not she realises it) is pretty key to whole evil debate. Quite frankly, living with Kitten would be MY idea of hell. The other hms seem intimidated by her - I'm sure they'd far rather be getting p*ssed, mud-wrestling & flirting - NOT getting mixed up in confusing pointless and uncomfortable rebellions. Every time Kitten leaves a group, they seem relieved - remember Marco and Emma (I think) discussing whether she could get access to anything pointy?
She scares them, she makes them feel uncomfortable, she intimidates the likes of Vic & Stu into feeling they have to prove their manhood by going along with her insanity.
I think BB probably knew EXACTLY what they were doing when they sent PsychoKitty into the house. I originally thought she was a plant, but now I realise that she's so stupid that she honestly thinks she's bucking the system when, in fact, SHE is the evil the producers had planned all along