Trent Harmon was crowned winner of Season 15 of American Idol — the last winner before the ABC reboot — and he learned some things he wasn't expecting to learn while filming the show.

One of those situations inspired his new song, "Her."

"One particular night I had to deal with the faithfulness situation," Harmon recalls, speaking of a memorable evening in Los Angeles when a girl was flirting with him. "I handled it as well as I could. I told the young lady, I said, 'I'm out here to do a job. I have a job right now. I'm on this show and you're sweet. Even though she hasn't been out here, I have a girl. I have a her. You can't be her."

That moment eventually inspired the idea behind "Her," which Harmon co-wrote with Jimmy Robbins and Laura Veltz. The Idol winner debuted the song during Big Machine Label Group's lunchtime showcase at the 2017 Country Radio Seminar and told a similar tale before performing the track alone on acoustic guitar.

"Over the last two years, I have had to be in situations and make decisions on my feet that I have never had to make in my whole life," he admits. "Fortunately, I've had the same young lady as my lady friend for the last six years. The last two years being on Idol I had to deal with some stuff ... to just put it out there, I had to tell folks no. 'No, I'm good. You don't have to come hang out with me tonight, I'm good.' And I wrote a song about it. It's called 'Her' and it says, 'You might be sweet and kind and you might think you're what I need, but you ain't never gonna be her.' This song means a lot to me."

Listen to Trent Harmon's "Her"

Another situation Harmon never thought he'd have to deal with while away from friends and family during American Idol was showing comfort in the time of a death. "I knew I had to stay well. And I knew I had to sing well and make it through. I never thought about having to stay faithful to my girlfriend or having to check in with my buddies who may have loss ... had to deal with death," he says.

Harmon's new album, You Got 'Em All, is out now. It features "Her."

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