The entire carriage fell utterly silent.
Quite a few of the older students recognized Dementors.
In the Wizarding World, Dementors were roughly the equivalent of the big bad wolf in the Muggle world, often invoked by parents to frighten naughty children: if you keep misbehaving, a Dementor will come and take you away.
Thanks to the tales spread by the Wizarding World's unscrupulous parents-and there were quite a few of those-Dementors had a fearsome reputation.
Yet this very Dementor, with its fearsome reputation, was simply gone?
Lupin was dumbfounded. Everyone in the carriage who recognized Dementors and knew how terrifying they were was dumbfounded.
Especially Lupin, who recognized the thing Harry was holding.
That object, as lustrous as a black gemstone but shaped like a bone, had a specific name in the Wizarding World: a Dementor Finger Bone.
Although its shape often bore little resemblance to a finger bone, it did appear in that form somewhat more frequently. The piece in Harry's hand, for instance, was a very typical example.
It was an important ingredient in many high-level Dark potions and ritual magic. It was extremely expensive, and even those willing to pay could not find any for sale.
That was perfectly normal.
Dementors were powerful magical creatures in their own right, and spells capable of dealing with them were rare.
Among the known spells that could effectively repel and injure Dementors without being quite so advanced, there was the Patronus Charm-and it had to be the corporeal kind.
Even in the Nastily Exhausting Wizarding Test, a corporeal Patronus Charm only counted for extra credit.
In fact, even a corporeal Patronus could usually only wound a Dementor rather than truly kill it. After all, the Patronus Charm was, at its core, a shield.
When this spell was first developed, its