The only females not worth inviting are Excella, Annette and Ashley. Excella and Ashley are highly annoying and Annette would probably think I am an Umbrella spy and try to shoot me. I'd even invite Alexia as long as she didn't have any viruses to inject me with.
But then again they'd probably all just kill me anyway because none of these women would willingly go to an all female PJ party hosted by mutant plant creature.
For a innocent party, I'd invite Rebecca, Sherry (kid), Claire-bear, and probably Helena.
For a fun party, Claire-bear, Ada, Jessica, and Leon.
For a really fun, as in drunken party, I'd invite, Rebecca, Sherry(Adult), Claire and Ada. Sherry would be b**** smacking Claire and crying because she never came back for her, Claire and Ada would be like freaking at each others throats for Leon, while Claire would be crying over Steve, and Rebecca would just be slurring her words and talking about Chris and Billy.
For a pillow fight that gets epic, I'd invite Jessica, Jill, Chris, and Wesker. Oooh the fun we'd all have... I wonder who'd be the first one to sneak a gun behind their pillow. xD