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Movies like The House of Confinement: Torture and Humiliation (2008)

Sachio was camping with his fiancée, Kiko, in the lush mountains, enjoying uninhibited sex even in broad daylight. That blissful time was shattered when a bizarre-looking man and woman suddenly appeared. When Sachio regained consciousness, he found himself bound to a chair in an unfamiliar room. As he worried about Kiko's safety, Sachio heard sounds from the couple. Voices that could be described as neither pleasure nor pain...