The master of the castle that served as the foundation for La Mancha Land in District 16. He is a First Kindred Bloodfiend and the Bloodfiend Elder in charge of District 16. His name is taken from Don Quixote, the protagonist of the novel Don Quixote. A First Kindred Bloodfiend of immense martial power, he overflows with confidence regarding his combat abilities, even boasting that he is the strongest. He possesses a fickle and childish personality despite the vast years he has lived. He frequently engages in immature and eccentric antics under the guise of having a 'good idea,' often causing Sancho significant distress. He is also an idealist who was the first Bloodfiend to dream of coexistence between humans and Bloodfiends. Originally, he lived a lethargic life with no interest in either race, but after meeting Bari—a human of equal strength—and hearing her stories, he embraced the ideal of coexistence. Thus, he built La Mancha Land, an amusement park where humans and Bloodfiends could play together, and even went further to travel the City as the first Bloodfiend Fixer. He is a white-haired male Bloodfiend characterized by his long hair, which, combined with his sharp Bloodfiend eyes, often leads people to mistake him for a woman. His clothing suggests a wealthy past, adorned with gold decorations, and he wears a uniform with sleeves longer than his arms.

A Bloodfiend of La Mancha Land holding the high rank of Second Kindred. In the past, she attempted to end her life, unable to endure extreme cold and loneliness, but was taken in by Don Quixote and reborn as his Kindred Bloodfiend. She has a rather cynical and realistic personality. Because she considers her savior and Sire, Don Quixote, to be her only true family, she resembles a rebellious teenage daughter who grumbles while remaining deeply loyal. She is frequently troubled by Don Quixote's immature and strange antics that he constantly proposes as 'good ideas.' Her weapon is the blood-channeling spear, La Sangre. She utilizes a blend of two martial arts: the Don Quixote-style blood-channeling inherited from her Sire, and her own modified Sancho-style variant. Unlike other Bloodfiends who simply shroud themselves in blood, she possesses superior proficiency, using it to reinforce her weapon or craft various armaments. Because of this, Don Quixote often uses spears crafted by Sancho rather than making them himself. She is capable of moving at incredible speeds, possesses the immense regenerative abilities characteristic of Bloodfiends, and like Don Quixote, has substantial mental fortitude. She never leaves Don Quixote's side.