Heen

"His name is Heen. He's my errand dog. I had him escort you here.
 * —Madam Suliman to Sophie"

Heen is the "errand dog" of Madam Suliman in Howl's Moving Castle. At first, Sophie thinks Heen is Howl disguised as an old dog to accompany her during her visit with Suliman. However, when she arrives, Suliman states that the dog is hers and was sent to escort Sophie to the castle. Heen later hops on the plane with the Witch of the Waste when Howl and Sophie are making their escape, and from then on helps Sophie many times during the film.

Personality
The Heen is silent and kind, happy

He also seems rather lazy, making Sophie carry him up the stair cases and really not doing too much afterwards.