Natsuko, the stepmother, treated her timid son Tadashi like nothing more than a toy. As always, no matter where he was, Tadashi had become nothing but a helpless plaything—his cock constantly erect, endlessly teased and controlled by Natsuko. This routine continued day after day, until one day, he began losing sight of his own feelings. Yet still, he had no choice but to depend entirely on Natsuko.