Virgo

Virgo the Virgin is a Celestial Spirit that is owned by Lucy Heartfilia and formerly owned by Duke Everlue. Virgo takes the form of a maid with shackles around her wrists.

Appearance
When Virgo was with the Duke of Everlue, she was of an extremely tall stature and overweight with a brutish face; Natsu referred to her as "Gorilla". Now that she is under Lucy's care, she has a more typical appearance of beauty with a petite body. She enjoys calling Lucy "princess".

Daybreak arc
During Lucy and Natsu's mission to retrieve and destroy the book Daybreak, Duke Everlue sends the biggest and most brutish of his maids (referred to as the "Gorilla Maid") to stop the duo from escaping with the book. Lucy, sensing the book is not what it seems, tells Natsu to fend off the maid while she learns the secret of the book. Duke Everlue tries to steal the book back, but when Lucy fights back, he summons Virgo, who turns out to be maid who was left to fight Natsu, and inadvertently Natsu as well, who hitchhiked with Virgo through the Celestial Spirit World (an unheard act that is forbidden to humans and considered lethal to attempt since there is no air in the Celestial Spirit World). Natsu, with Lucy's help, defeats Virgo, though the act is later attributed entirely to Lucy, to Lucy's dismay when she unsuccessfully tries to clarify with the truth.

Lullaby arc
During the Death Lullaby arc, Lucy and her friends are unable to nullify the magic wind wall when Kage is severely injured. When Natsu suggests using Celestial Spirits to bypass the wall through the Celestial Spirit World, Lucy rejects the idea while Happy reveals that he has Virgo's key. With Duke Everlue's arrest, Virgo decided that their contract was null and decided to give her key to Lucy (through Happy). While Lucy is initially reluctant to accept, Happy reminds her that Virgo is capable of diving underground, which may allow them to go under the magic wall to the other side. Lucy accepts and is stunned that Virgo, when summoned, takes the form of a petite and pretty maid who apologizes for causing trouble during their previous encounter. Virgo explains that out of loyalty for her owner, she changes her appearance according to their wishes. When Lucy suggests that their contract be arranged later, Virgo addresses Lucy as "Mistress" and "Your Highness (Dominatrix in manga)" (Lucy rejects both) before settling on "Princess". She dives underground to create a hole to allow Lucy, Natsu, and the mages escape the magic wind wall and upon emerging on the other side, she protects Lucy's undergarments from being seen, though has little regard for her own.

Galuna Island arc
Lucy summons Virgo to use the Celestial Spirit's diving ability to create holes for traps. When Lucy compliments Virgo's ability, Virgo believes that Lucy is punishing her until Lucy shouts that she was praising Virgo. Virgo also makes use of her diving ability to capture the Headman of Galuna Island and save him from being killed by the poison jelly dumped over the village..

Oración Seis arc
After Lucy defeats Angel, she and Natsu tumble over a waterfall. When Lucy awakens, she finds Virgo has appeared without Lucy summoning her and has tended to Lucy and Natsu's injuries as well as providing them with new clothes. Lucy, while grateful, worries that her magic must be low since Virgo managed to summon herself without Lucy's command.

Magic and Abilities
Like her former master, Everlue, she can use diving magic, which allows her to dig into the ground or other solid substances as though they were water. It is unknown whether this is her own original magic, or if she learned it from Everlue, but more likely the former.

She also has the ability to change her apearance to suit her master's tastes, as seen with her first seen hulking form with formidible brute strength. It is currently unknown if her strength scales with her size or if she has the same physical prowess in her current form, as Lucy has of yet used her for combat purposes.

Trivia

 * Virgo has a tendency to ask whether she should be punished after she has done something regardless of if it was good or bad, possably indicating she enjoys being punished.