As Pion, revealed to be a robot who the heroine now calls P-ko, joins the party, they encounter her companion Oyage, a similar robot who calls himself O-taro, who wants to abandon his mission and live in the strange city. As he sends a killer digger truck after them, they all fall down a hole, winding up at an underground castle. The heroine and assistant are confronted by O-taro, who combines with the slimes to become a 'Killer Death Cat', though the fairies step in to help them...