Melanie Lynskey stars as Rose on Two and a Half Men.  Rose is Charlie's neighbor and after a one time fling becomes his full fledged stalker.

Rose, despite her craziness, is actually quite intelligent and went to both Princeton and Stanford.  Rose moved away to London but still makes the occasional appearance.

Rose Quotes

...We're both like two lonely socks that want desperately to keep someone's feet warm, but we don't match up with any other socks. So all we can hope for is to be a dust mitten or a hand puppet

Rose

Charlie: I thought we agreed we were just friends.
Rose: We are. We're friends who slept together once, and then one friend never called the other friend, but luckily the other friend forgave him.
Charlie: Where are you going?
Rose: To make my friend a grilled cheese sandwhich.
Charlie: Rose, Rose, I don't want a grilled cheese sandwhich.
Rose: Would you prefer a quesadilla?
Charlie: That sounds nice

Two and a Half Men Quotes

Yeah, hi. I'm watching your commercial cash for gold and you just showed a woman selling her wedding ring for $500. No, I don't want to sell gold, I want to meet her. She's hot and we know her marriage isn't working out.

Charlie

Charlie: Oh, try MalibuPuddingGirls.com.
Alan: Pudding Girls?
Charlie: Trust me.
Alan: Oh ... ew.