A creeper is someone who creeps.
Creeping is somewhere between a healthy admiration and unhealthy stalking.
It has been proposed that a majority of Knox spends their time eating, sleeping, and creeping.
Mailroom workers are known to be the creepiest people on campus. They know what mail you get and who sends you packages at all times and pretty much anything else you would need to stalk a person, e.g. box #, middle name, age, home address, home phone #s, etc...