Keroro Gunsou is the main protagonist of the anime and manga series 'Keroro Gunsou' (also known as 'Sgt. Frog'). He is the leader of the Keroro Platoon, a group of frog-like alien invaders from the planet Keron. Despite his mission to conquer Earth, Keroro often gets distracted by his love for Gundam models and other earthly pleasures. His comedic antics, laziness, and eccentric leadership are central to the series' humor and charm, making him a beloved and iconic character.