Monica Geller is a little bit crazy, but definitely seems to be the leader of the group of Friends. She's Ross's sister and high school best friends with Rachel and kind of ties to the group together as a mother-like character.
Monica is known for being a little OCD and for being overweight in high school. Now? She's a bit of a chef but holds various jobs during the season.
At the end, Monica ends up marrying Chandler in season seven.
Ross: Hey. Oh, oh, how'd it go?
Phoebe: Um, not so good. He walked me to the subway and said "We should do this again!"
All: Oh. Ouch.
Rachel: What? He said "We should do it again," that's good, right?
Monica: Uh, no. Loosely translated "We should do this again" means "You will never see me naked."
Rachel: Since when?
Joey: Since always. It's like dating language. Ya know, like, "It's not you" means "It is you."
Chandler: Or "You're such a nice guy" means "I'm gonna be dating leather-wearing alcoholics and complaining about them to you."
Phoebe: Or, or, ya know, um, "I think we should see other people" means "Ha, ha, I already am."
Chandler: No, no, no, no, no, no. (Opens the door for Monica) No. Monica, it's Sunday morning. I'm not running on a Sunday.
Monica: Why not?
Chandler: Because it's Sunday. It's God's day.
Monica: Okay, if you say stop, then we stop.
Chandler: Okay, stop.