Kreacher

Kreacher is a fictional character in the Harry Potter series who first appeared in Harry Potter and the Order of the Phoenix. Kreacher was a House-Elf who was forced to keep many secrets for the Order of the Phoenix, as he stayed at their headquarters, Grimmauld Place.

The family Kreacher served was the "Noble and Most Ancient House of Black". When Sirius Black was the only male member of the house of Black left, Kreacher was forced to serve him. According to Dumbledore, Kreacher's existence under Sirius was as miserable as Dobby's with the Malfoy family.

The name Kreacher is a pun on "creature".

As Sirius Black was not a dark wizard like the rest of his family, Kreacher hated him and was not happy working for him. Kreacher seized his chance to leave when Sirius told him to "get out". He left the house and went to a member of the Black family he still had respect for: Sirius's cousin Narcissa Black, also known as Narcissa Malfoy, the wife of Lucius Malfoy and the mother of Draco Malfoy.

Lucius Malfoy, under orders from Lord Voldemort told Kreacher that if Harry Potter were to contact the house by means of the Floo Network, he was to lie and say Sirius was not there. Since Kreacher did not belong to Harry, he could lie to him without having to punish himself. Kreacher later turned up in the attic and Sirius was convinced he had been there the whole time.

Kreacher followed Malfoy's plan, and it succeeded. Harry went to the Department of Mysteries to save Sirius, as he believed he was in trouble. Sirius Black, who later went to the Department to help Harry, was killed in the struggle there by his cousin Bellatrix Lestrange.

In Harry Potter and the Half-Blood Prince, Harry inherited Kreacher, as Sirius had died and left all his possessions to him. This inheritance to Harry, and not Bellatrix (Sirius's eldest living relative), was confirmed valid, when Kreacher obeyed Harry's command to "Shut up." Harry did not want to keep Kreacher, and immediately ordered him to work in the Hogwarts kitchens with other House-Elves. At Hogwarts, Kreacher's despisement of Harry came into conflict with Dobby's awe of him causing them to got into a number of fights, much to Peeves's delight. When Harry needed somebody to follow Draco Malfoy to find out where he was disappearing to, he was helped unwillingly by Kreacher and willingly by Dobby. They came back to him with the important information that Malfoy was going to the Room of Requirement.