Doctor Mouse

When the Tenth Doctor and Rose Tyler visited the Paws 'N' Claws pet shop, they discovered that it was being run by a group of settled, peaceful Cybermen who had converted a group of Mice into Cybermice. The defeated the Cybermen and considered helping the Cybermice, before realizing that a mouse dressed much like the Doctor was already fighting the other mice. The Doctor and Rose left, agreeing that K9 was the only pet that they needed on the TARDIS. (COMIC: Untitled)