I'm either making assumptions or building lore. Take your pick.
Holecia, the Soul Shepherd
She is sleek and black, with feathered wings and a white belly. Her body is lithe, with a long neck and four legs. Her front claws are opposable like hands. She has a pair of white antlers that sprout from the top of her head and curve forward. Her antlers shed every year, and she has taken to keeping them through the years. To her, they are like discarded fingernail clippings, but to the people who live around her roost they are quite valuable and she likes to give them as rewards for great deeds.
Her breath is white soulfire. It burns not flesh and hair, but one's very soul, growing as it leeches the spirit of whoever touches it. After the fire has spread, Holecia can inhale it to absorb the stolen energy back into herself.
She roosts atop a plateau in a savanna populated mainly by more literal sheep herders and the like. The sheer walls of the rock formation are pockmarked with holes bored in by the surrounding people, each just big enough for a mummified body to be placed in. The spirits of those entombed here are bound to Holecia, and she draws strength from them. In return, she ensures their rest, and protects both their spirits and their bodies from looters or necromancers.
Holecia is a generally benevolent force. She is soft spoken and compassionate to those she meets, though she doesn't seek out the needy. Just as she protects her people, she draws power from them, and her strength is directly proportional to their population.
The Holecian Clans: A motley and varied collection of families and peoples who inhabit the plains surrounding Holecia's roost. They have their own governance, and are not always on friendly terms with each other, but they all share the protection of Holecia. They range in size from nomadic shepherd groups, to grand cities.
The Soul Brand: No matter what culture, all clans in Holecia's domain go through a rite of passage in which they travel to her roost, scale the tomb-embedded cliff face, and pay homage to the Soul Shepherd. She brands them with her soulfire, leaving a mark somewhere on their body and taking in some of their essence. With this imbibed essence, she recognizes their spirit, and makes an accord to protect it in death, after their mortal time has come. In return, the mortal in question loans her a small portion of their living vitality, contributing to her strength. It is a minuscule amount, but the essence given by all of her people combine to a great power.
Children who die before receiving the brand are mourned for doubly, and are buried at home with whatever protections for their spirit the family can muster. For this reason, sick or weak children are often pushed to take the rite of passage early. Some die on the journey, and some are consumed by the soulfire. Holecia will personally inform the families of the latter cases. It is truly horrifying to see the Dragon Lord Holecia descend upon your clan stead after sending a youth to her.
Ancestor Bells: Each clan has a great wrought iron bell in their clan stead, engraved with the names of all of their dead, and enchanted by Holecia. The bells make no sound unless rang by a member of the clan they belong to. When rang, it summons the spirits of those whose names are writ upon it, who will rush to the aid of their clan in times of need.
The ancestors use the living vitality of the ringer to assume a quasi-corporeal form. The ringer is almost always killed.
How the one to ring the bell is chosen is different between clans.
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