March 25, 2013
Keroro gets a cavity for eating too many sweets and not brushing enough. However, Keronian cavities are caused by a microscopic alien race and must be exterminated from the inside. Kururu uses an invention to shrink Giroro and Tamama, and they go inside Keroro's mouth to beat the cavitians. Giroro and Tamama try but there are too many enemies for the two of them. Another attack to the cavitians is organized, this time with Fuyuki, Natsumi and a robot with Keroro's conscience in it. They advance into the enemy base only to find the leader of the cavitians waiting for them. Keroro orders a retreat but he stays thinking he has a weapon that could end the battle but in fact the whole robot is a bomb that Kululu detonates.