Shadow worshipers of the Devourer under the Cruorlena and Umbrarex -Prompt #17 a religious order founded or based in your world’s history

Prompt #17 a religious order founded or based in your world’s history – Shadow worshipers of the Devourer Highest servants are the Cruorlena (blood queen) and Umbrarex (shadow lord) Priest-mages are called the Umbracruors Siren-Priestesses are called Cruortrixes Sacrifices of blood, life-glow, sex, and even children are required to gain favor for petitions to be granted the great temple at the Gate of the Devourer in the city of Umbrahemos Templos is where most are offered. There are several other temples on Xelusia. The Temple of Anthemusa is the training temple for Umbracruor and Cruortrixes, and the place where the Xelusians rediscovered the lost magic of the Sirens, which almost won the Second Kingdom War.
The legends claim a pair of siblings seeking wealth in a cave found the Devourer and opened the Shadow Gate to his realm, they became the first queen and king and their souls have been passed down along the royal line of the Xelusians for tens of thousands of years. The truth is far more terrifying. The Cruorlena and Umbrarex are actually extra-dimensional beings who indwell the chosen vessel and demand blood sacrifices and life sacrifices to honor their parent deity. Considered the Daughter of the Devourer and the Lord of Shadows, these two entities move from generation to generation enslaving and sacrificing the people of Xelusia and harvesting their life-glow to feed their god. The Queen is considered the true ruler of Xelusia and controls her people through a form of magical seduction/manipulation called Siren's Magic. Only those with oracle, shepherding, or healer's magic can resist. The entities also taught the Xelusian people the use of blood magic and that by consuming blood and its life-glow they can access the power of the person whose blood it is. However, use of blood magic often causes insanity in those with warrior magic, and a craving for more blood like an addiction in almost everyone else. The Cruorlena also uses her magic to harvest sexual energy and suffering from her subjects. The sibling of the indwelled one is always sacrificed to seal the entities the chosen body. If the Cruorlena is bound to a weak willed host, the host will go insane with blood craving and lust and have to be put to death, or will go insane from grief and pain and kill themselves.
When the Dark Oracle was indwelled by the Cruorlena entity, she over came it and remained in control of herself. She mixed the Shining magic of the oracles with the Sirens' seduction magic and for the first time many Xelusians felt what it was like to be loved unconditionally. This earned her the loyalty of the population of Xelusian during her time as the Cruorlena. The Dark Oracle's suspected murder by the first princess caused civil war that lead to the great Cataclysm.
Excerpt from The Huntsman of Adamos
Yurieth watch the Cruorlena walking around her rooms, she had just come from the Temple of Shadows where she had killed four Aetherian warriors and filled her blood altar with their blood. Afterward, she had their bodies treated in profane ways. The Black Huntsman had watched the Ruling Royals of Xelusia for over a tenday and he wanted nothing more than to burn this entire city to the ground. In the temples, mothers brought their children to be bled into the blood altars or used in ways that were against every Aetherian teaching. There were no husbands and wives as on Aetheria, nor families that he could discern. Every night there seemed to be some kind of blood rite and orgy somewhere in the city. If Yurieth had believed in the infernal realm where the dishonored spent eternity, he would have believed this place to be its gate. As he watched a group of Royals leaving the Cruorlena's rooms, he noticed the Umbrarex left her as well, which Yurieth found odd. He had never seen the Cruorlena alone. She walked out onto the balcony and looked down at the Celebration of the Day of Darkness. His gaze followed hers to the debauchery going on below. Tomorrow would be the Day of Light Returning on Aetheria , the most holy day of its calendar year, and Yurieth resisted the urge to wish he was home. He felt the tingle of Siren's magic and looked back to the Cruorlena. She was staring at him with peach-glowing red eyes. ‘Hello, Son of Adamos.’ The power washed over him like an avalanche, and he almost submitted. There was a vibration in the air and Yurieth dove off the building as a blast of magic smashed where he had crouched in the shadows. Landing in the crowd, he ducked among the partiers. Suddenly, the siren's magic shook the air like the tone of a large bell. Everyone stopped moving and turned their head toward the Queen. “Bring me the Huntsman who walks among you alive. Your Queen has use for him.” The mass of people turned as one searching for him, so he ducked down a dark alley. The power of the siren magic was a thousand times worse than the most painful headache he had ever had. There were no sounds except the footfalls of the mindless searching for him. A crowd rushed toward him from a side street, and more from doorways. A naked woman jumped on his back as two tackled his legs. He fought free of them as the crowd surrounded him. It seemed like hundreds of hands were grabbing and hitting him at once. He twisted to get free, slashing with his long knife and ax. His bow was pulled from his back as he was lifted and then pressed flat against the stone street. The sheer numbers of bodies pressing down on him paralyzed his efforts and crushed the air out of him.

Structure

Highest servants are the Cruorlena (blood queen) and Umbrarex (shadow lord) Priest-mages are called the Umbracruors Siren-Priestesses are called Cruortrixes