Hiroaki Mizusaki is a Japanese manga artist and writer, known for creating the comedy manga series Miss Kuroitsu from the Monster Development Department. Mizusaki is the sole author and illustrator of the series, which began as a one-shot published on Flex Comix's Comic Meteor website in April 2019 before becoming a full serialization later that year. The series follows Tōka Kuroitsu, an assistant in the Monster Development Department of an evil secret organization, navigating workplace challenges such as budget constraints, management demands, and tight deadlines while creating monsters to fight superheroes.

Before creating this original work, Mizusaki contributed to other manga projects. From 2013 to 2016, Mizusaki illustrated the manga Strike Witches: Dai-501 Tougou Sentou Koukuudan, a four-volume series in the Strike Witches franchise, which was published in Kadokawa's Shōnen Ace magazine. Mizusaki also contributed as an artist to the 2016 anthology comic The Short Story Collection of Switching Bodies with a Girl.

The success of Miss Kuroitsu from the Monster Development Department led to a twelve-episode anime television adaptation produced by the studio Quad, which aired from January to April 2022. The series was broadcast on ABC and TV Asahi's ANiMAZiNG!!! programming block, with Crunchyroll handling licensing outside of Asia. The manga concluded with its tenth compiled volume, released in March 2025.

Mizusaki's artistic identity is characterized by blending workplace comedy with tokusatsu and superhero genre elements. Miss Kuroitsu from the Monster Development Department uses the framework of a villainous organization to satirize corporate culture, focusing on relatable office struggles such as proposal presentations, inter-departmental competition, and adapting to last-minute changes from leadership. This approach transforms what could be a straightforward action premise into a character-driven comedy about professionalism and perseverance.