Navy is the name given to one of the rubies amongst the Ruby Squad.
Navy resembles a standard Ruby, her gemstone located on her stomach and her outfit the standard diamond associate uniform, with a triangle opening for her gemstone. Unlike the other rubies, she has a more blue tint to her color rather than the standard red.
Amongst the rubies in the squad, Navy is the more aristocratic member, acting in a polite and fancy manor towards others, and takes a liking to a number of planets and what they have to offer. She holds a similar sort of behavior to Rarity in this asspect.
Despite the friendly and fancy nature, she has shown a rather michevious side to her, showing when she convinced the Crystal Gems to get her squad off of Aredox, throwing them for a guilt trip to do so, and if things go more critical, she will not hesitate to fight and even shatter someone just to stay alive, acting almost horrifying in these circumstances.
While not really brought up or said directly, Navy has shown to be a rather successful escape artist, and has shown on more than one occasion to get out of deadly situations. These include her escape from Aredox, and her somehow escaping her holding cell on the White Diamond Space Station.
Navy joined her troop on the trip to Earth in order to investigate the Tunguska Gem Facility. When they first see the Crystal Gems, it was her who tried to get the squad in the right direction by asking Sapphire directly. While there, she was apart of the B group (Herself, Ruby, and Leggy), and she explored the facility with them at first until she was switched with Army half way through.
Navy became a major character during this special. During a trip to the V System, she ended up caught by Aredox, but managed to escape in a spaceship pod with her gemstone cracked, and making her unstable upon landing in Equus. She immediately attacked Rarity on the spot before she passed out, and was brought to Twilight Sparkle's library, where she explained the situation to both Ponies and Gems. She only got them to help her when she made a guilt trip on Flint. Despite this, she stayed behind and waited it out until they've returned with her team.
Navy became trapped thanks to White Diamond, thanks to the information Jade received by Eyeball, though while the others were locked away, she managed to escape and avoided getting recaptured by the Gem Hybrids. As she escaped, she ended up finding the human group aboard the ship through a vent, and after figuring out what they were up to, she got them to help her out, saying she'll fly them out of the ship herself so long as she stayed with them and help her break out her squad. She stayed with them from there, though she ended up captured again once she ended up in Chamber 77. She did eventually escape with everyone else, only to crashland on another planet.