MC PriUsa is a rabbit-themed mascot and announcer within the AiPri system of Onegai AiPri. Their primary role is to energize and facilitate live AiPri performances, serving as a charismatic host who introduces idols and keeps the audience engaged. The character is consistently high-energy and always maintains a lively, upbeat demeanor, with a signature catchphrase used to start live shows. MC PriUsa embodies the whimsical, high-spirited atmosphere of the Pretty Series and acts as the public face of the AiPri organization. In terms of their function, they are a constant presence during live events, providing commentary and helping the competition progress smoothly. They interact closely with the main human idols, notably Konomi Inori and Aoi Yumemiya, during stage appearances, and also coordinate behind the scenes with the mysterious character Fortu to manage the flow of events. As a mascot character, MC PriUsa does not undergo a traditional character development arc in the sense of personal growth, but their role expands in scope as the AiPri competitions grow larger and more complex throughout the series.