shoulder creeper
The obnoxious sort of person that peeps over your shoulder when you are working on a paper or sitting at the computer.
"God, I can't stand my co-worker, Lethareau... He is SUCH a shoulder creeper."
"I walked past Bob when he was on the internet, and I totally shoulder creeped to see if he was looking at porn... again!"
"I walked past Bob when he was on the internet, and I totally shoulder creeped to see if he was looking at porn... again!"