EDIT: RIMR just pointed out to me that 'gimp' means something not-so-funny in the US. Here's the European definition from urbandictionary.com:
A male BDSM rubber/leather slave. Specifically refers to slave in full body suit - e.g rubber/leather enclosure suits, and (this is the key thing) a full head mask.
'Ah, I see you've brought your gimp along. Doesn't he look sweet with that ball gag in his mouth? I hope he's well behaved.'