Hematomancy, apparently. Connected to another grim San Antonio case.

Police: Woman captive for four days, blood drawn for witchcraft ritual

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The abducted woman, recalling that the two believed in some type of witchcraft, watched them begin a ritual on her. Tristam Smith cut off some of her hair, the warrant states, as her finger and palm were cut because Smith needed blood for the ritual.

The warrant states the ritual was performed because Angel Salazar’s sister wanted to know if the woman had anything to do with the death of her brother.
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