There once was a girl called Maia.One day Maia found a puppy, dying in the snow. Maia took the puppy to a vet and when the pup was better, named him Black. Maia was rich and so, when not playing together, Black was the guard dog that protected Maia from all sorts of threats. Maia also took self defense lessons.
On a cold, wintery night a Maia aged 18 had a run in with 3 kidnappers. Black did the best he could but the kidnappers had come prepared with ways to neutralize the guard dog. Then the fire started and consumed all those in reach.
Maia and Black died together, one ashamed for failing his master and the other with thoughts of revenge. They were reborn in hell together; a baby demon and her loyal baby hellhound. Black refused to be separated from Maia, even in hell.
They aged and grew in strength for many centuries. Man's best friend, a lonely girl's most loyal companion.
Maia took the demonic rankings by storm, having a high aptitude for all things demonic. Never were they ever separated, even when millennia had passed.
And that is the story of a girl and her dog.