The House of Confinement: Torture and Humiliation (2008)

Sinopsis

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...