Cancer

Cancer, "The Giant Crab", is a Celestial Spirit that is one of the 12 Golden Zodiac Keys. His key is currently owned by Lucy Heartfilia.

Appearance
Cancer looks like a funky hairdresser. His hair is black and braided in red cornrows that end in a shape that resembles crab's pincers. Like Warren Rocko, he has thick lips. He always wears a blue striped shirt and dark trousers with two aquamarine stripes each side, also wearing boots in his feet. In his pants there's a ring chain in the right pocket and a hairdresser tools' bag in the left side of his belt. He wears a golden necklace and it's commonly seen with his two main weapons: Scissors. The color of his eyes is unknown because Cancer always wears sunglasses with green lens. He also has six crab legs that appear from his back.

During the fight of Lucy against Flare Corona, Cancer appeared with a different outfit, maybe because of Lucy's activation of Second Origin. He now wears a coat designed with Cancer's symbols on it. Also he wears shoes instead of boots, and his scissors are larger and more rectangular. Despite less sharp format, the scissors were able to cut a very powerful Hair Magic spell.

Personality
Cancer has a very "cool" personality, he isn't very emotional or hotheaded.

Happy first thought that Cancer would end his sentences with the word -kani (crab); however, Cancer actually says -ebi (shrimp) at the end of his sentences. This shocked and displeased Happy. In the anime, Cancer acts differently when in the presence of Erza. He acts in a gentlemanly manner and ends his sentence with -choki, meaning snip instead of -ebi. Erza made this suggestion during the struggle against Eisenwald. . Her "not abolishing the opposition" and strict personality made a giant impression on Cancer that he even gave her a flowers once.

History
Cancer used to be owned by Layla Heartfilia. Before her death, she passed on her keys to different owners. Eventually, when she became older, Lucy Heartfilia was given Cancer's key, along with Aquarius.

Daybreak arc
Cancer is first summoned to fight Duke Everlue. However, he thinks he is being summoned to give Lucy a haircut. After the confusion ends, Cancer helps Natsu Dragneel defeat him by cutting off what is left of Everlue's hair and mustache.

Lullaby arc
Lucy summons Cancer to get rid of the remaining Eisenwald members (and also to make a good impression on Erza). He cuts through several of the enemies' weapons with his scissors.

Galuna Island arc
Lucy summons Cancer again to battle the Moon Drip worshippers. He seems to have gotten a small crush on Erza, as he presents her with roses before following Lucy's orders, much to Lucy's chagrin.

Tower of Heaven arc
Cancer is briefly used to defeat some tower guards by giving them bald haircuts. He also provides Lucy with new clothes from the Spirit World.

Oración Seis arc
Cancer is briefly used by Lucy, along with Taurus and Sagittarius, to stop the Naked Mummy Guild from robbing the Love & Lucky Guild in Acalypha. Once again, he defeats the dark guild members by giving them bald haircuts.

Edolas arc
Cancer is briefly used to cut Lucy Ashley's hair, and asked her if she really wanted that, because in Earth Land, girls don't do that too often.

Tenrou Island arc
Note: Events in this arc occur only in the anime and do not constitute canon material. During her fight with Kain Hikaru, Lucy summons Cancer and asks him to give him an embarrassing haircut. Cancer does what he is told but fails when the toughness of Kain's hair destroys his scissors. Kain then defeats him with his Dodoskoi attack, sending him back to the Celestial Spirit World.

X791 arc
Cancer celebrates Lucy and her friends' return from Tenrou Island when Virgo brings them to the Celestial Spirit World. During the celebration, he does Wendy's hair.

During the Grand Magic Games, Cancer is summoned by Lucy during her fight with Flare Corona, when he successfully nullified Flare's Hair Shower - Wolf Fang and cut a good part of Flare's hair.

Magic and Abilities
Scissors: Cancer is Lucy's hairdresser because of his weapon which seems to be two large pairs of scissors, with crab-claw design handles, which he can also use to cut hair. Lucy uses Cancer to cut her hair or make a new hair style for her or her enemies. Cutting an enemy's hair seems to knock him out. It is also shown that his scissors are sharp enough to cut through weapons such as swords and hammers.

After Lucy powered up by unlocking her "Second Origin," Cancer apparently gets a new, different pair. This pair of scissors is longer, with a square-tip, and doesn't have a crab-claw design on the handle.

Immortality: As a Celestial Spirit, Cancer cannot die, unless he is forced to stay in the Human World somehow. Furthermore, as its owners magical strength grows stronger, so does Cancer.

Happy in Boots
Cancer appears as Happy's third gift to the king and princess of the kingdom along with Virgo.

Fairy Academy - Yankee-kun and Yankee-chan!
Cancer assumes the role of being Lucy's hairdresser. He is called to do Erza's hair for her date with Sieg of Era Academy. Cancer also appears as part of the Fairy Academy staff during the assembly called by Carla for the delinquent students, though it is unknown what is actual role in the staff is.

Major Battles

 * Lucy Heartfilia (owner) & Natsu Dragneel vs. Duke Everlue
 * Erza Scarlet & Lucy Heartfilia (owner) vs. Eisenwald Guild Members
 * Natsu Dragneel, Lucy Heartfilia (owner), Gray Fullbuster & Juvia Lockser vs. Tower of Heaven Guards
 * Lucy Heartfilia (owner) vs. Naked Mummy
 * Lucy Heartfilia (owner) vs. Kain Hikaru
 * Lucy Heartfilia (owner) vs. Flare Corona

Trivia

 * Lucy's quote when summoning him is: "Open the Gate of the Crab! Cancer!".