When a dude is looking over your shoulder at your computer screen with their face way too close to yours.
A sign of repressed homosexuality.
I was just trying to enjoy a youtube vid, but my roommate crept up behind me and pulled a close face.
When a person has a few drinks and feels the need to talk to you with their face almost toucing yours.
On holidays this dude would get drunk and close face everyone no concept of personal space it was horrible.
When you look into another person's face very closely, so that their eyes merge together into one eye. This was illustrated in an episode 9 of season 3 of the Adult Swim tv show "Moral Orel," by Dino Stamatopoulos.
I like to sneak a look at your closeface before kissing you.