Sharon Osbourne ruined her niece's party with a stripper who used his own genitals as a wristwatch

Sharon Osbourne's flair for flamboyance led to total disaster at her niece's bachelorette party -- and we're talking the kind of nightmare from which you never quite recover.

The "X Factor" judge was excited to help plan her English niece's bachelorette party. In an attempt to add some pizzazz to the affair, she hired a male stripper for the event, despite knowing that her niece is "a very nice girl," she said.

It did not go over well.

"The stripper came in and of course I told him who was the bride-to-be," Osbourne told The Sun. "And he was doing his thing, and he stripped off totally naked. She was sat at table and he went behind her and put his penis on top of her head -- she had long hair and he got her hair and he was wrapping it around his penis."

Sorry, it doesn't end there:

"Then he stopped that and stood right at the side of her and he said, 'Can you tell me what time it is?' But he had wrapped his penis around his wrist," Osbourne said. "She started to cry so bad, she was sobbing and shaking, and I had to take her outside. I felt so bad."

Lesson of the day: Don't put Sharon Osbourne in charge of party-planning, unless you're curious about the mechanics of a willy wristwatch.

Filming is currently underway for next season of "X Factor," where Osbourne judges alongside Simon Cowell, Louis Walsh and Nicole Scherzinger.