facebook etiquette - Knowing when to hit that 'ask me out' button and when to run

Knowing when to hit that 'ask me out' button and when to run for your life because you’re being haunted by someone you barely know.

Hey, I’ve been staring at your profile for 2 hours. Can we go on a date? I mean, like, a real date.

You're on Facebook. That means you're single. So I'm asking you out. I'm not even mad.

I just friended you. I'm probably going to ask you out. I hope you're ready.