Shinta Mizumura, son of a deceased Kyushu shrine head priest, was raised by his grandfather after his parents' death. Following his grandfather's advice, he attends Saint Ritsumei Academy in Tokyo. Physically, he presents as an average-height teenage boy with brown hair and hazel eyes. His personality blends kindness and shyness with striking obliviousness to romantic advances. This trait defines his interactions with childhood friend Chizuru Makimura—who harbors deep feelings for him—and Lilith, who actively pursues him. Shinta shares an especially close bond with Chizuru dating to their middle school years. They attend the same high school class and frequent companionship leads others to mistake them for a couple. Though partially aware of Chizuru's affection, he questions his worthiness and remains uncertain about the extent of her feelings, occasionally blushing at her overtures while wrestling with self-doubt. When those he cares for are endangered, his typically meek demeanor shatters into vengeful protectiveness. This transformation surfaces violently after learning Plum harmed Chizuru—prompting Shinta, previously nonviolent, to assault Plum, astonishing both witnesses and himself. His existence pivots upon meeting Romanian transfer student Lilith, revealing his heritage as the last descendant of vampire slayers while exposing her as his vampire nemesis. Their fates interlock through Lilith’s need to conceive a child with him, then kill both to bathe in their blood for survival, forcing Shinta to confront his legacy and inevitable destiny.