K9 (A Rose by Any Other Name)

A model of K9 lived with the Tenth Doctor in The TARDIS. He was on board when the Doctor adopted a cat, who he named Rose. The two did not get along.

Biography
The Doctor first got this model of K9 after his loss of Rose Tyler, during which time he settled down and stopped traveling. (COMIC: A Rose by Any Other Name)

K9 (A Rose by Any Other Name)