Ciosa is a character from the magical girl anime series Majokko Megu-chan. In the original Japanese version, this character is known as Chousan. He is an investigator or inspector dispatched from the Witch World, the magical realm from which the main characters originate. His primary assignment is to monitor the progress of the two young witches competing for the throne, Megu and Non. However, rather than acting as a neutral observer, Ciosa is portrayed as an antagonist who actively seeks to undermine and sabotage the efforts of one of the candidates, specifically Megu.

Ciosa has a distinct and somewhat comical appearance that reflects his lackadaisical and untrustworthy nature. His personality is marked by laziness, disloyalty, and a mean-spirited desire to see Megu fail in her quest to become queen. He is not above using underhanded tactics or aligning himself with more dangerous enemies of the witches to achieve his goal. Some descriptions characterize him as a perverted or untrustworthy figure, whose actions are driven more by a personal grudge or petty malice than by any sense of duty. He lacks the noble or heroic traits of the main protagonists, serving as a source of conflict that is separate from the primary rivalry between Megu and Non.

In the story, Ciosa acts as an agent of the Witch Queen, but he abuses his authority. His role is to cause trouble for Megu and to skew the competition in favor of the other main rival, Non. He is not a powerful witch himself, but he possesses magical abilities that allow him to create obstacles and schemes for Megu to overcome. His position as a supposed official from the Witch World gives him a veneer of legitimacy, which makes his interference more complicated for Megu to deal with directly.

Ciosa is rarely alone and is typically accompanied by two talking animal underlings who assist him in his plots. One is a sly-looking Siamese cat and the other is a crow. These companions share his antagonistic disposition and help him carry out his various plans against Megu and her family. Unlike many other characters in the series who undergo significant development, Ciosa remains a consistently negative and scheming figure. His machinations often backfire or are resolved by Megu's own growth and determination. Ultimately, his behavior is officially recognized by the Witch Queen, and he faces formal punishment for his misconduct as an inspector. Despite his lack of redeeming qualities, he provides a recurring source of comic relief and low-stakes conflict that contrasts with the more serious trials Megu faces.