Barney Stinson: How do you keep a girl from becoming a girlfriend? The rules for girls are the same as the rules for Gremlins.
Ted Mosby: Gremlins?
Barney Stinson: Gremlins. Rule 1: Never get them wet; in other words, don't let her take a shower at your place. Number 2: Keep them away from sunlight; i.e., don't ever see them during the day. And rule number 3: Never feed them after midnight; meaning she doesn't sleep over and you don't have breakfast with her, ever!
Ted Mosby: What about brunch. Is brunch cool?
Barney Stinson: No, Ted. Brunch is not cool.