Pierre used to work part-time as an amusement park mascot inside the Froggie costume—which is pretty funny when you consider he's actually a prince from somewhere overseas. He's got golden hair and admittedly pretty features, though most people only knew him through that bulky frog suit for a while.
He ditched his home country to escape a succession dispute over the throne, which he managed by pulling off what he framed as a casual visit to Japan. Seems like it stuck.
Despite his royal background, Pierre comes across as genuinely bright but also kind of innocent about how the world works. What drives him is pretty straightforward: he wants to use whatever power and skills he has to make people smile. It's not a complicated goal, but it's clearly genuine.
Content compiled by AnimeList.moe from publicly available sources.