I'm so like Monica. I hate messes, I just can't leave it, I would have to get up and clean it up, if it was mine or someone else's, i clean it up! lol. I also like to be really organized. My books on my shelf are arranged from my favorite to my least favorites. My Disney tapes are in alphabetical order, yes I still have mine, and my DVDs are also arranged from favorite to least favorite. I don't know, but that's just easier for me. My mom is the exact same way, so that's probably where I got that from. lol
But Monica's cleanliness just makes her, her. Before she was adult, she wasn't like it. It also happens as you get older too. My older sister wasn't so OCD about cleaning until she had her own apartment. I mean she likes the remote in one spot at all times. She has everything where she wants, and when you move it, you have to put it back where you got it. lol.
So as you see, as Monica got older and started to lose weight and take care of herself, she developed a little OCD. But it doesn't make her a bad person or crazy. That's just her. And that's okay. At least someone out the friends is organized and clean. lol
my sister is just like her though. She always tidies up when she comes round. You'll put something down and she'll put it in it's right place within a second :P