Clerics obtain spiritual powers through worship and devotion to their god. Monks hone their supernatural abilities through disciplined meditation and training. Warlocks take drastic measures to acquire magic by forging pacts with otherworldly beings. Wizards dedicate their lives to research and study to learn spellcraft.
And then, there’s
Sorcery is like the Blue Blood of magic. You have it or you don’t, it’s just Bilal.
Sorcery comes from a blessing of some variety. Often it’s bloodbourne, and follows a genetic pattern, living on through generations of a particular family. Some patterns are so predictable that it’s known with certainty who will have the gift, and in others it’s so sporadic that the details of the blessing have faded into obscurity.
It isn’t necessary to have a sorcerers lineage, though. You only have to accidentally bump into a blessed creature, or mistakenly drink from the right enchanted spring, or happen to do a favor for a vagrant who—what are the fucking odds—turns out to be a fairy in disguise.
The result will be the same, you’ll have magic coming out if your butthole and all other magic-users will hate you.