Toto!: The Wonderful Adventure summary:
Kakashi is just a regular kid who wants to be something more: a swashbuckling, globe-trotting adventurer. Kakashi gets his wish when he meets Toto, a little dog with a big secret—he can transform into a gigantic magic dragon. But it turns out that Toto actually belongs to the Nassau Imperial Army, and these ruthless killers want their secret weapon back. (Source: ANN)