This motel owner secretly watched his guests have sex for thirty years.

Gerald Foos describes himself as “the greatest voyeur in the world”.

In the 1960s, he purchased The Manor Motel in Colorado. Fuelled by an “uncontrollable desire to peer into other people’s lives,” he proceeded to transform the premises into a pervert‘s dream.

Of the 21 rooms in the motel, 12 were fitted with fake ceiling vents through which Gerald and his wife, Donna, could observe the most private moments of their guests. The ceiling vents were located above the motel beds, but extra “viewing posts” were installed in the bathroom, lest Foos miss anything important.

“This trial-and-error process took us weeks,” he told The New York Post. “And it was exhausting — with me constantly going up and down between the attic and rooms, and my hands aching from all those adjustments with my pliers.”

He was careful to ensure that only young, attractive couples were accommodated in the “viewing rooms”, with families and the elderly relegated to the remaining nine rooms.

In the thirty years between purchasing the motel and selling it in 1995, he watched hundreds of couples engage in sex, often having sex with his wife while they spied on strangers through the ceiling peep holes.

But he's not ashamed of his crimes, and insists that other people should be thankful for his "sexual research and social observations."

His "research" consists of sordid diary entries and crude statistics. His records, as disclosed to The New York Post indicate that he witness 296 sex acts, 184 male orgasms and 33 female orgasms over his thirty years at the motel.

He writes that 12 per cent of the couples he observed were "highly sexed", 62 per cent had "moderately active sex lives", 22 per cent had "low sexual drive" and 3 per cent had "no sex at all".

Foos' written observations, such as this one disclosed to The New York Post, are detailed and graphic.

"Finally after kissing and fondling her, he quickly gained an erection and entered her in the male superior position, with little or no foreplay, and orgasmed in approximately 5 minutes," he writes of the first sexual encounter he observed. "She had no orgasm and went to the bathroom."

He also claims he has witnessed rape, robbery, suicide and even a murder - although the details of the murder he described do not seem to line up with any crime on record in Colorado.

Foos is now writing a book about his experiences, The Voyeur's Motel, to be released on July 12. The statute of limitations on his crimes has passed, and as a result, he can no longer be charged.

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