‘American Idol’ contestant reacts to Katy Perry calling him ‘so hot’ during audition She called him a "dreamboat" and invited him to hang out with her.

When Trevor Holmes walked into his audition for “American Idol,” he knew he was going to have to perform in front of Katy Perry, his all-time celebrity crush, but he didn’t expect her to swoon over him.

"I am singing my heart out and she is there, flirting with me," Holmes said today on “Good Morning America.” "You can't really put it into words."

For his audition, which aired Monday on ABC, the 27-year-old part-time construction worker from Thousand Oaks, California, had to sing in front of “Idol” judges Perry, Lionel Richie and Luke Bryan.

As soon as he walked in, Perry started flirting with him and called him a "dreamboat" at one point.

"Everybody growing up, you always have this celebrity crush that you never think you will actually meet," he said.

Holmes, who said he works in construction to help support his mother who has lupus, sang "In Case You Didn't Know" by Brett Young for the judges. For a special touch, he added Perry's name to the lyrics.

Perry even told him that if he didn't win the coveted ticket, which sends contestants on to Hollywood for the next round in the competition, he could still hang out with her.

"You are so hot!" she said.

The audition took an interesting turn, though, when Holmes received his ticket to Hollywood. His girlfriend, Sierra Nielsen, who had been waiting outside with his mother, ran in, cutting off Perry who had gotten up to hug Holmes.

"I was fully supportive of it [the flirtation]. We all have celebrity crushes," Nielsen said on "Good Morning America." "We had so much fun and Katy and I hugged and we laughed about it and I even told her, 'We can share him.'"

At the end of the audition, Perry said, "If you love it, let it go and then it will come back and marry you."