Simon Cowell felt "like a schoolboy" around Dannii Minogue, amid reports they had a secret affair.
The music mogul has reportedly spoken out about his feelings for the Australian singer during her time working with him as a judge on the UK version of The X Factor.
The revelations are made in The Intimate Life of Simon Cowell, a book written by BBC journalist Tom Bower. In the tome, to be published next month, Simon addresses his relationship with Dannii.
"I had a crush on her. It was Dannii's hair, the sexy clothes and the t*ts," he said according to the Daily Mail.
"I was like a schoolboy. She was foxy. She was a real man's girl. Very feminine."
The book claims Simon, 52, had more than just a crush on the singer as "it was genuine love".
However, Simon was not ready for a relationship as he had just split with long-term girlfriend Terri Seymour, according to the book.
It claims Simon pursued Dannii when he chose her for the new X Factor judging panel in 2007.
The same year he confessed he was checking out her assets in a photograph.
"Dannii reckons there's a picture on the X Factor website where I'm staring at her bottom," he said.
"I probably was... but I think most people would if they were sitting next to her. She was probably sticking it out on purpose.
"Every guy in the world fancies Dannii. She's become a sex symbol since joining the show, and the contestants love her. She's got that Sophia Loren, movie-star sex appeal, I love sitting next to her."
The pair fuelled rumours of an affair after they were pictured seemingly holding hands in the back of a car in 2008. Dannii hit back at the claims saying they were doing no such thing.
"We were not holding hands. But no one believes me. It was the angle of the picture," she said.
The two were said to be dating before Dannii, 40, got together with Kris Smith, the father of her 21-month-old son Ethan. They split this month after four years together.
Dannii appeared on the X Factor from 2007 to 2010. Simon left in 2011 to launch the talent show in the US.