This series opens with Goji64 and Koji fighting the Kuike Brothers. The Kuike Brothers beat Goji64 and Koji to a pulp, even managing to cripple Goji64 by breaking his ankle. The boss known as The Great Demon uses his shrink ray to shrink the nearly dead Koji down to human size, in an attempt to get Koji out of his way for his plan of turning the whole Earth into his own hell. A group of scientists know as the S.K.S.A. discover Koji and nurse him back to health, introducing him to Japanese foods and teaching how to speak Japanese. The Great Demon sends two of his Human Sized Kaijin after Koji, just to make sure he dies. The two Great Demon Kaijin: Kaiji and Zekk. Koji battles them both and for a breif moment Koji turns into a hulking brute and beats down on the two Kaijin, forcing them to retreat.