Of course, Neptune doesn't really need a diving suit, but she couldn't pass up this free full permission one by Aley Resident. For a limited time you can get it from Davy Jones' Locker on the sea floor at Whimsy Kaboom.
Neptune herself took this photo. She calls it "Neptune Spies Her Super Ho Girlfriend Undersea."
OMG! I cannot believe I made that typo! Super HOT! Super HOT!