Tom: Yo Eric, did you get a fresh kill last night?
Eric: Nah, but I did bang this girl that I used to see in college.
Tom: Oh well, don't worry, nothing wrong with a repeat offender
A customer, who habitually returns purchases, for no good reason, other than to be a complete pain in the ass. During the original purchase, they bombard the salesperson, with questions regarding refund and return policies. So frequently and with such conviction, the salesperson can almost predict them coming back within 48 hours or less. This process can possibly go on for months, before it is finally resolved. Easily spotted, because everything they say about the product is jaded and pessimistic.
"That guy's my 'repeat offender'. Send someone else to deal with him. On second, thought? FUCK THAT SHIT. Throw his ass out, and call the cops if me makes a fuss!"
Sleeping with someone whom you've already slept with in the past with no intentions of making it into a relationship...
Also assuming that it's an open invitation to sleep with when you encounter them.
"It's ok he's just a repeat offender, it doesn't really count."
"Oh, yes you're getting laid tonight. You don't have to try so hard. It's already in the bag because you're a repeat offender."