The Gimp Suit, which is a bondage suit clearly modeled after those associated with BDSM culture, is as an all-black rubber/PVC bodysuit, with a red strap-on dildo harness on the crouch (with no attached accessories) and black rubber/PVC boots. As are other "Special" outfits, the player's watch, eyewear, necklace and hat are still visible while donning the Gimp Suit, as the Gimp Suit is simply added over the player's top, pants and shoes, if any.
The Gimp Suit is prominently featured during "Key to Her Heart", when the player must seduce Caligula's Palace croupier Millie Perkins by participating in her BDSM activities. The suit is first worn after the player character obtains it at the Redsands East sex shop, and wears it up until the player meets Millie face-to-face and completes the mission. Completion of the mission will add the Gimp Suit into the player's wardrobe.
In addition to allowing the player to clear any wanted level when worn, the Gimp Suit can be worn to speed up the increase of the player's relationship with Millie; instead of going out on dates, Millie will have the player enter her house for more sexual sessions if the player chooses to meet her in the suit, increasing the player's relationship with Millie by 10 percentage points in each encounter. In other respects, the suit has no effects on respect and sex appeal, or on other girlfriends.
- The Gimp Suit is likely to be named after the Gimp, a character from 1994 film Pulp Fiction who wears a similar outfit.