In the central city of Tanagra, which is ruled by the enormous computer Jupiter, Riki was held captive in the Eos Tower, the residential area of the privileged class. He was kept as a pet by one of the most elite artificial beings, a blonde individual known as Iason Mink. Despite having his freedom and dignity stripped away and undergoing inappropriate training, Riki refused to be tamed and resisted those around him. Then, one day, while Riki stood in front of the heavily guarded entrance gate of Eos, a door that should never have opened suddenly did. In this unprecedented escape event initiated by Riki, Iason was faced with a dilemma...

In the outskirts of the pleasure city, Midas, lies the special autonomous district of Keres. Within the harsh class-based society, this area, situated at the lowest rung, is commonly referred to as the Slums. Riki, who had been returned to his old stomping grounds in the Slums by Iason after three years, reunites with his former comrades. Among them is Guy, the only partner Riki ever opened up to. Riki, who once led the delinquent group "Bison" and exuded an overwhelming presence, returns to the Slums, accompanied by unpleasant rumors spreading throughout the area. Despite not offering any explanations, Riki occasionally displays a troubled expression. Guy senses a subtle transformation in Riki's demeanor.

Kirie, the new addition to Guy's group, harbored a sense of rivalry towards Riki, who had returned to the Slums. Riki, coerced by Kirie, agrees to go to a pet auction where humanoid pleasure toys are being offered for sale. Unable to forget his past humiliations, Riki becomes increasingly frustrated by Kirie's behavior and his expressed desire to "rise to the top." On the other hand, Iason, who had released Riki and refrained from having a pet, was also headed to the auction venue upon the recommendation of a fellow Blondie, Raoul. In a city adorned with extravagance and desire, Riki and Iason once again cross paths...

Riki unexpectedly reunites with Iason at the pet auction venue. Unable to conceal his shock, Riki drinks at a run-down shot bar on the outskirts while vividly recalling bitter memories of pleasure and suffering. It all began three years ago on that fateful night. Riki, a streetwise Slum mongrel, would steal valuables from the crowds, then race through the unending nightlife of the city of Midas. Seeking both sustenance for survival and the thrill of the hunt, he scouted for easy targets. Suddenly, someone grabbed his wrist from behind. With a chilling tone, the one who had captured him was none other than Iason, a Blondie who stood at the pinnacle of the privileged class...