X Factor contestant Kitty Brucknell worked as a honeytrap for a private detective agency, it has been reported.
The singer, who wowed the judges on Saturday's episode of the show, sang Lady Gaga's Edge Of Glory before being voted through to the next round.
Dalbir Virdee told the Sun he watched the ITV1 show and recognised Kitty as the same woman who approached him three years ago after being hired by his ex-wife.
He said she contacted him online before arranging to meet him on a date at upmarket store Harvey Nichols in central London.
He said: "I had a feeling I was being set up. We had champagne, which she spilled down her front. I realise it was a ploy to get me to rub it off her."
Mr Virdee said photographs of him with Brucknell were later used in his divorce.
Brucknell, 26, from Cheltenham, Gloucestershire, was one of the stars of the first episode of the hit show which was watched by a peak audience of 12.6 million - matching the record for the highest viewing figures for the opening night.
The show saw the debut of new judges Gary Barlow, Tulisa Contostavlos and Kelly Rowland, who joined veteran Louis Walsh.