Sent by the parent company as an auditor to a subsidiary suffering from poor performance, Shiori is a fastidious woman who views sex as filthy and detests it intensely. However, her attitude is actually a facade concealing her own deep-seated sensitivity—especially her strong fascination with anal stimulation—and company president Fuse sees right through her. Recognizing this hidden desire, Fuse begins to train and dominate Shiori's anus, aiming to possess her completely and mold her into his obedient plaything.