The Enclave is a magical organization for only women. It is led be a mysterious person referred to as The Vale. It is believed that only women possess the magical ability to cast spells. This is not true but that is what is believed. Unknown to most people but, males can cast spells. The problem is the Enclave will hunt down and kill any male that casts spells and will hunt down and kill any female that casts spells that is not part of the Enclave. They control all spellcasting. They cast a vale over the whole process.
People from the Enclave travel and behave as if they are above the law. They roll into area to gather up new members at young ages. They often add new females at or about the age of ten. For some reason they never join members of the Demon Hunters to fight the demons. They do not seem to get in the way, but they do not help fight the demons directly. They do help indirectly with resources and information. Leaving the nitty, gritty of hunting to mundane folks.
The Enclave have one known facility. It is located in the coastal city of Gaddel. This is a free Citystate. Officially a city council runs the city, but most suspect that the Enclave really run it. Gaddel is located south of Eadwald. It takes anywhere from one week to one month depending on how you travel.
Most people would have no idea how magic works. All casters must have a spell disk to cast spells. This disk is called a Writ Arcanum. See the Spellcasting section of the players handbook.