Arturo the Swift was never really wanted by either of his parents. His father was a traveling Varisian (with no name that Arturo's mother recalls) who had had too much ale one night and bedded an impoverished woman (also Varisian) in Absalom. That woman was Nerina, Arturo's mother. Nerina herself was swept off her feet by the exotic man before her, but never intended their joining to be repeated. The consequences were not to her liking...
Unloved by his mother, and scorned by her family and friends alike, Arturo took to the streets at the tender age of nine. Much to their relief, he often tells himself, though he has no real way of knowing. He has long since forgotten where his mother lived. His only friend on the streets was a scorpion he managed to capture (in a muddy jar) that he named "Sandoval". It wasn't until much later that Arturo's bond with Sandoval became much deeper and more mystical.
Arturo lives now only through sheer determination, and a not insignificant portion of luck. The determination he attributes to his harsh early life. The luck, Desna. Arturo often relies on his goddess to bless his endeavors, perhaps too often. Arturo is a thief of no small talent, though, and was beginning to attract the attention of the law.
It was only after his most recent escape that he thought about getting off the streets. The constabulary almost had him, and it was only "good fortune" that he fell through the roof that he was running away on and into a running sawmill. When the authorities saw the grizzly scene, they thought Arturo dead - and he nearly was. While they searched for the owner to let them in to retrieve Arturo's remains, someone dragged Arturo's unconscious and blood-soaked body to an underground hospice, where he was abandoned to the harsh but competent administrations of the healers there. When he recovered some six months later with all his limbs intact, he took it as a message from Desna: his luck had limits and he needed to change his life.
Thus it came to pass that Arturo the Swift sought employment elsewhere and came upon the Grand Lodge of the Pathfinder Society...