Penny's mom, Prudy. Is she....
I might be reading too much into this but I love sublimimal jokes and I want to see if I'm right on this one
Is Penny's mom, Prudy, a prostitute? some of the quotes are hinting in that direction (the quotes mignt not be EXACTLY right but they have the general jist of it):
Edna: It takes a lot of effort to get out your personal stains...
Seaweed: (untying knots) was your mom in the navy? *I think that's a s&m joke, if you don't know what that is, sorry for destroying your innocent minds*
Penny: (about a room) I don't even know why this room is here *I know it's a bomb shelter but it could be a sex chamber as well*
Prudy's also really catholic so she could be overcompensating...it's psychalogical stuff