Lucy has brown eyes and shoulder length blonde hair that is usually tied by ribbons in a variety of colors in a small ponytail to the right side of her head with the rest of the hair loose. However, in the year X791 she appears to keep her hair up more often in pigtails. She is buxom, and a curvaceous body. Her (presumed) measurements are: bust, 91 cm; waist, 59 cm; and hip, 88 cm (37in, 23in, 36in). These measurements were later revealed to be slightly different, with the breasts being two centimeters less, and the others one less.
Her pink Fairy Tail stamp is located at the back of her right hand. Additionally, Lucy does not consistently wear the same outfit. However, she always has a belt that, along with keeping her skirt up, holds her Celestial Spirit keys and a whip with a heart-shaped end. She also wears black, leather high heeled boots. She also bears a striking resemblance to her mother.
Lucy takes exceptional pride in her appearance and is very confident in her sex appeal, often exuding a certain amount of vanity. Despite this superficial attitude, she is a clever, kind, and genuinely caring person. Lucy is passionate for literature and is in the process of writing her own novel about her adventures with Fairy Tail although she does not like telling anyone about it. Aside from her interest in writing and reading prose, she also likes shopping, cooking and assertive men. Her favorite colors are blue and pink. She is a member of the Heartfilia family, once one of the wealthiest and most influential conglomerate families in the country of Fiore. However, due to her estranged relationship with her father and the death of her mother, Layla Heartfilia, she left home to follow her own path, which displays an ambition for independence.
Lucy is very kind to her Celestial Spirits, and refuses to utilize them as shields or think of them as such. She fights alongside her Spirits and treats them as friends, unlike several other Celestial Spirit Mages, who view them as mere tools and objects. Lucy cares greatly for her Spirits and will also go to great lengths to give them happiness, even at the cost of her life. Despite technically being an owner of the Spirits, she refuses to be addressed as such, and instead prefers to be called their friend. Although, Lucy is, in most cases, cowardly and easily frightened, she has no problems with fighting and would happily stand up to danger, even if she ends up getting hurt, for her friends and guild. While her powers are normally not as overwhelming as her teammates, Lucy has proven to be a capable combatant herself, often using her cleverness to her advantage, and thinking outside the box during battle. She has eventually inherited Natsu's stubbornness and refusal to give up, even when all the odds are against her favor.
Lucy usually freaks out at her guildmate's antics. Unlike most of her friends, she does not get very excited about fighting and is not quick to resort to violence as the solution. However, she does admit that being around her guildmates is really fun. Being a Celestial Mage, Lucy always keeps her promises. She gives her all for the sake of her guild and friends.
Celestial Spirit Magic Lucy practices Celestial Spirit Magic, which allows her to summon Celestial Spirits, Magical beings residing in the Celestial Spirit World, using the Keys of their respective Gates. When summoning a Spirit, the Keys are enveloped with a soft, golden light. Once a contract has been made with a Spirit, such Spirit will be available for Lucy to summon on certain days, in which it will fight on her side and perform several tasks for her. Her Celestial Spirits have varying levels of power, with different ones being more suited for certain tasks than others, not necessarily related to battle.
For example, Aquarius can control the water, creating powerful waves which can sweep away large amounts of foes, while Taurus has enormous physical strength, making for a valuable melee fighter able to flank Lucy during battle and tackle opponents on her behalf. However, Celestial Spirits are sentient beings who possess personalities and traits, and are thus able to act accordingly during battle, sometimes even ignoring Lucy's orders and acting on their own, something which is usually portrayed in a comical way (such as Aquarius acting arrogantly and catching even Lucy herself in her attacks, or Taurus having perverse tendencies about her).
Lucy has explained to Natsu Dragneel that Celestial Spirit Mages have the potential to obtain extremely rare Gold Keys, which open the gates of the "Ecliptic Zodiac", and common, store-bought Silver Keys. According to Lucy, while there is a large number of Silver Keys, there are only 12 Gold Keys, each of them being related to a specific astrological sign. So far in the series, Lucy has obtained 10 Gold Keys and 5 Silver Keys, a considerable amount of Keys for a single Celestial Spirit Mage. Lucy's ability to summon her Spirits is limited by how much Magic Power she has to sustain them; the more (and more powerful) Spirits she summons, the more of her Magic is exhausted.She has been shown capable of using five of her Ecliptic Zodiac Keys in one day, a noteworthy feat. Lucy has also demonstrated the ability to summon Celestial Spirits only by calling them instead of using the keys.