Sergeant Keroro, who is ”58th Planet of the Gamma Planetary System, Space Invasion Army Special Tactics Platoon Leader,” infiltrates the Hinata family's home as a preparatory stage to conquer Earth, but is easily captured by Fuyuki and Natsumi due to his inherent incompetence. Keroro ends up staying in the home of the Hinata family thanks to Fuyuki's generosity, or perhaps simply out of his curiosity. As they pass the days keroro and his four subordinates together plot to conquer Earth, or maybe not.