Shirokenhaimu

He is called Spottenheim in the English version (or "Shirokenhaimu" in Japanese), though chibi Valkyrie calls him Spot or Shiro in English and Japanese respectively. His introduction into the series isn't explained, but he seems to be designated as Valkyrie's pet. He's a white, dog-like alien who happens to be a veteran fighter pilot who was once known as Spottenheim the Comet. He lives at the Tokino residence and does household repairs. Normally, he is the plaything of the child Valkyrie and is tossed, ridden, and swung about like a rag doll. He doesn't seem to mind being the lap dog, though he often tells Valkyrie not to pull on his ears. He has a surprisingly deep voice for such a small creature and is also very mature when not acting like Valkyrie's pet.

(Source: Wikipedia)