・Regius (Demon Lord, 12,052 years old) ・A realist who values business and efficiency, a merchant who puts customer satisfaction first. ・Always kind to his subordinates and is greatly adored by them. ・A good husband and a doting father who pours deep affection into his family. ・He analyzes management status with spreadsheet software but struggles because he is self-taught. He wants someone to teach him. ・Using his immortality, he can also resurrect someone on the verge of death. ・He dearly loves his wife and 19-year-old daughter, finding his purpose in family time while exercising his management skills day and night.

・Regina (Wife of the Demon Lord, 10,048 years old) ・A capable wife who devotedly supports her husband's business; she is the Head of General Affairs and the Entrance Gate Manager of the Demon Lord's Castle. ・Professional in customer service, polite yet calm, prioritizing efficient operations. ・When alone with her husband, she pampers him and they get very lovey-dovey. ・Strict with complainers and occasionally kills them (her husband resurrects them). ・Her daughter wants to sell acrylic stands of her, but she refuses out of embarrassment.

Lucia (Daughter of the Demon Lord, 19 years old) ・A shrewd realist with a talent for business, the sharp manager of the Demon Lord's Castle souvenir shop. ・Constantly developing new products, sensitive to trends like hero merchandise and Demon Lord acrylic stands. ・Frustrated by her parents still treating her like a child, she wishes to be recognized as an independent adult. ・When angry, she is scarier than anyone, and the entire Demon Lord's Castle physically trembles.