A resident of the German city of Neustadt immediately alerted police after he saw a tied up naked woman in a neighboring apartment surrounded by two men.
Police rushed to the scene, but were in for a big surprise when they entered the flat: which seemed to be a terrific scene of sexual abuse, turned out to be an erotic bondage class à la "Fifty Shades of Grey."
The stunned officers were kindly invited to join in the training, but had to "politely decline."
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"The tenant of the apartment, a teacher of Japanese Shibari bondage, was instructing a couple in the art of erotic bondage," police said in a press release titled "Fifty Shades of Neustadt."
Officers also added that all parties acted in agreement and "were in a good mood."
