Why Would Fluffy Come from “a Greek Chappie”?

FLUFFY IS HAGRID’S PET DOG, GUARDIAN OF the
Philosopher’s Stone after it is removed from Gringotts Bank:
Rowling describes him in Harry Potter and the
Philosopher’s Stone as “a monstrous dog, a dog that filled the
whole space between ceiling and floor. It had three heads; three
pairs of rolling, mad eyes; three noses, twitching and quivering in
their direction; three drooling mouths.”
J. K. Rowling says that Hagrid bought Fluffy
from “a Greek chappie I met in the pub.” That makes sense, because
Fluffy is actually a magical creature from Greek mythology known as
Cerberus. He was a sentry there too. He guarded Hades, the
underworld, where the souls of the dead go to live for eternity. It
was his job to keep all living beings away, and to eat anyone
trying to escape.
According to some legends Cerberus had one hundred heads. In others, snakes
also grew from his necks.
See also: Centaurs
Sphinx
Cerberus, from an illustration drawn about AD 1500.
CERBERUS AND HERCULES
Cerberus plays a role in a famous Greek myth, the
story of the twelve labors of Hercules. The hero Hercules had been
tricked by the goddess Hera into committing horrendous crimes, and
was punished by becoming a servant to an unworthy king for twelve
years. The king demanded that Hercules complete twelve tasks
considered impossible. Most of them involved killing or capturing
vicious beasts, like the Hydra, a creature with many heads. The
last, considered the most difficult, was to capture Cerberus from
his post at the gates of Hades and parade him before the king.
Amazingly, Hercules did so, using just brute strength.
CERBERUS AND MUSIC
One other person got the better of Cerberus, but
it wasn’t with muscle. Orpheus, a gifted musician, braved the
underworld to rescue his beloved, Eurydice. Lacking the strength of
Hercules, he played his lyre to tame Cerberus. It worked. He was
able to sneak by the creature, and to escort Eurydice away. That’s
why the Greek chappie told Hagrid music is the way to tame
Fluffy.
