Natsumi, One Week Without Anger / Keroro, Invasion is a Second Stomach?

Synopsis

«Natsumi: A Week Without Anger» Always being scolded, a frustrated Keroro proposes to «store up Natsumi's anger energy and use it for the invasion.» His real goal is... «Keroro: Is Invasion a Second Stomach?» Keroro thinks the «second stomach» (room for dessert) that Aki and Natsumi have, but Fuyuki doesn't, might be the key to invading Pekopon...