Tarquin

Tarquin, styled Lord Tarquin, is a Prince-Prior of the Holy Terran Chantry and a member of the ruling triumvirate alongside Emperor Alexander VI and Amon Kosis at Fort Din during the siege of Gododdin. Hadrian identifies him as "the black priest" among the three, and the Cantor Yod stands at his shoulder throughout the crisis.

Tarquin's humanitarian council proposals prove to be a calculated trap designed to force Hadrian to open the ancient vessel Demiurge. When Hadrian refuses, Tarquin publicly accuses him of condemning the civilian population and turns the council against him.

His political position collapses when he is brought before the Emperor's sarcophagus in a formal court session. Appearing in black armor and painted white for the occasion, he denies possessing a daimon, calls Hadrian a demoniac, and refuses to kneel until he is forced to crawl. The Emperor deliberately exposes him to a plague by forcing him to kiss an ulcerated, infected hand. Tarquin is then escorted out by Excubitors with his helm sealed over his face to contain the infection.