Lately, Mari has been having recurring erotic dreams. Strangely, it's always the same dream: a man wearing a horse mask appears, threatens to kill her unless she allows him to penetrate her with a vibrator, and she writhes in both fear and pleasure as she's forced into sex. Even while emphasizing her role as a maid, she is dominated by her masked master, climaxing repeatedly. Her feelings, physical reactions, and the hidden truth beneath Mari's erotic dreams are vividly revealed. Entwined with BDSM elements, the scenes gradually lead her deeper into ecstasy. Here lies a special experience that feels like it can only be tasted within her dreams.