Santori, known as "The Peak," is a Colonel leading the Inquisition's elite Thaumaturges. A tall, bearded figure with long limbs, he perpetually holds his left palm vertically in a prayer-like pose, even while asleep. His face remains largely hidden beneath a wide-brimmed hat and a beard segmented by thick rings. He wears a short poncho-style robe over brightly patterned breeches, creating a stark contrast between his grim upper half and vibrant lower attire. Overgrown fingernails and grizzled hair on his calves suggest unkemptness, yet beneath his robes, a lean, muscular build covered in scars is visible, with gnarled joints.

Despite his age, Santori exhibits a boisterous, excitable personality. He frequently expresses enthusiasm through loud laughter and maintains a positive outlook. A notable speech habit involves listing past experiences or accomplishments before declaring the present situation surpasses them all. He particularly enjoys challenging battles, becoming visibly angered when opponents disappoint him. A history of surviving perilous encounters leaves him seeking formidable adversaries to reignite his fervor, as seen in Cyfandir.

His primary ability, a "Miracle," projects magnified replicas of his body parts or entire form. These projections emanate from a sigil on his back, mimic his movements, and can disintegrate most matter. Damage or restraint inflicted on them partially reflects onto his actual body, potentially causing self-harm. While mobile, he projects individual limbs for attacks; stationary, he generates multiple limbs or a full replica. The projections are durable but dissipate if sufficiently damaged, requiring time to recreate. Achieving maximum projection size requires assistance from fellow Thaumaturges Ullmina and Liselotte, indicating their powers can combine for amplification.

During the Cyfandir conflict, Santori confronted Seth. Initially disappointed by Seth's perceived shortcomings, their battle escalated into a philosophical clash where Seth challenged Santori's adherence to the Inquisition's ideals, questioning who was truly enslaved. The confrontation ended with Santori's defeat and death.