Medoki is a human vampire hunter who also works as a store clerk in his grandfather's shop, which specializes in vampire extermination goods, custom costumes and weapons for hunters, and anti-vampire security products. He is frequently partnered with Shōka, a fellow hunter, and the two are close in age. Medoki's helpful and caring nature led him to become Shōka's partner almost unconsciously, and he often takes on the role of her caretaker. He is sometimes nicknamed "Shōka's caretaker" by others, and the vampire Draluc has referred to him as the person who is sometimes in the background. Medoki is a member of the Hunters Guild, holding a B-rank classification. He is also known as the "Inventive Hunter" because he occasionally invents new products—both for his own use and for others—using his creativity and practical skills.

Medoki has a quiet and understated personality, to the point that he has been ranked first in a list of the "hardest hunters to find on earth" due to how plain and unassuming he is. Despite this, he is dependable and loyal, particularly to Shōka. He has a gentle, somewhat self-effacing demeanor, and one of his minor quirks is that he finds women who are self-conscious about having a flat chest to be cute. This is revealed under unusual circumstances, but it reflects his generally nonjudgmental and accepting attitude.

His motivation stems from a sense of duty as a hunter and a desire to support his family's business. He does not seek fame or recognition, instead focusing on doing his job competently and helping those around him. His role in the story is that of a supporting character who provides practical assistance in vampire-hunting missions, often supplying gadgets or backup. He is a good friend and reliable partner to Shōka, and his interactions with other characters, such as the main protagonist Ronaldo and the vampire Draluc, are typically low-key but contribute to the series' comedic tone—especially when his plainness is highlighted.

Medoki does not undergo significant character development over the course of the series, remaining a consistent side figure. His key relationships include Shōka, with whom he works closely; his grandfather, who runs the shop; and fellow hunters like Kameya, who jokingly acknowledges Medoki's unobtrusiveness. He also interacts briefly with Draluc and Ronaldo during joint missions.

In terms of abilities, Medoki is a skilled vampire hunter equipped with standard hunting weapons and tools. His standout trait is his inventiveness: he designs and crafts specialized vampire-hunting items, some of which he sells in the family store. He is also a capable combatant, having earned a B-rank in the guild. No supernatural powers are attributed to him; his strengths lie in his resourcefulness, his knowledge of vampire weaknesses, and his ability to work effectively as part of a team.