[Happens when you're a perpetually bored god/hero who makes more trouble than you're worth everywhere you go.]

Hm...well, from what he says, he wasn't actually born a dog. He was just named after one in his lifetime. Then he died, got summoned to be someone's familiar spirit, and since the kid didn't have enough power, he turned into a dog.

[At least, that was what he said. For all anyone knew, he could have been a dog with the ability to turn human.]