Keroro (character) skips out on destroying military planes in a simulated reality in favor of buying the newest Gundam model with Fuyuki Hinata. As they head home, they encounter a mystery shrine resembling a space fort. As Keroro prepares to give a monetary offering, he accidentally drops a 100-yen coin into the shrine, forcing him and Fuyuki to go after it. Inside the shrine is a prehistoric-looking jungle, where Fuyuki finds an ancient dome and a small glass container, inside it a glowing orb. As Keroro triumphantly finds his coin, he knocks over the container, which breaks, causing the orb to shine wildly. After Keroro attempts to fix the container with rubber cement, the duo dashes out of the shrine and toward home, leaving the remaining piece of the container to transform into a pink