Crux

Crux,"The Southern Cross", is a Celestial Spirit owned by Lucy Heartfilia. It is unknown if Crux can be used for combat purposes. However, it is known that Crux has the ability to search for information about Celestial Spirits and their owners by sleeping, though he's forbidden to reveal too much, as one's activities are still a private matter in the Spirit World. His full name is Crumudgeon.

Appearance
Crux resembles an aged celestial spirit. His head beholds a giant, metal cross with floral-like golden patterns. He also has a white-haired mustache sprouting from his nostrils that also appears like a tiny crosses. Oftentimes he closes his eyes but he will eventually open these if he found his objective. He seems to be wearing a medieval-like outfit, complete with green pants and wooden pointed shoes. His arms and legs are skinny, and appears to be orange-tan like. On his arms are blue-colored knots attached to his wrists and elbows.

Crux is currently missing a tooth and he favors to levitate than to stand.

Personality
Crux doesn't talk too much. This can result from his restraint. He also often falls in sleep.

Loke arc
Crux is summoned by Lucy to see if Loke had any history with a Celestial Mage before. During his meditation, he finds out that Loke once knew Karen Lilica but didn't divulge that Loke was really Leo. He is later summoned again with the rest of Lucy's spirits to persuade the Celestial Spirit King to spare Loke's life.

X791 arc
Crux celebrates Lucy and her friend's return from Tenrou Island when Virgo brings them to the Celestial Spirit World. During the celebration, he shows Levy McGarden a collection of books, which fascinate her. He allows Levy to take a book with her, and then falls asleep again.

Magic and Abilities
Scanning: Crux is an expert on Celestial Spirit Magic. He knows all that's going on between humans and the spirit world, and can thus scan past people who have been in contact with Celestial Spirits and Celestial Mages. While he's doing that though, he falls asleep.

Levitation: Crux after calling constantly hovers in the air.

Immortality: As a Celestial Spirit, Crux cannot die, unless he is forced to stay in the Human World somehow.

Fairy Academy: Yankee-kun and Yankee-chan!
Crux is seen cleaning the pool grounds during Aquarius's swimming class. He also chastises Virgo while she digs up pitfall traps on he school grounds. Crux and the other Celestial Spirits make up the school staff of Fairy Academy.