Chris Harrison has been promoting The Bachelor‘s ending as “phenomenal” and “mind-blowing,” but it also may end in some serious heartbreak. Contestant Caroline Lunny, who was pegged an early frontrunner on Arie Luyendyk Jr.’s season, is not happy with the race car driver.

During the taping of the Women Tell All special, she revealed exclusively to Us Weekly that during her time in the house, she made Arie a mixtape — all of her favorite songs put onto a USB. Later, she learned he listened to it with another woman. “I found out he later used it in the fantasy suite. I’m friends with Becca and she told me! She was like, ‘Oh my God we listened to your thing,’” Caroline explained. “It’s fine because he knew that we were really close, but I was kind of, like, ‘That’s a little off-sides buddy, playing my fu—ing mixtape.’”

Additionally, Caroline called out Arie in a new sneak peek for the reunion special.

“So, I mean this whole time you’ve said that you’re here because you’re trying to find a wife,” the 26-year-old realtor begins, while Arie nods. “I know what you did, and I don’t know how you could do that. And I just really don’t understand, but I really hope you found what you’re looking for.”

He answers by saying, “I think that’ll play out in the weeks to come,” but she cuts him off. “You don’t need to answer me but I needed to say it,” she said.

While she couldn’t explain exactly what she was referring to, she did tell Us afterward that she felt she had to say something, as she was “upset with him on behalf of a friend.”

“I think we all want to have that moment where we’re like, ‘Hey, you fu—ed over my friend, f—k you,’” Caroline told Us. “I think everyone who has ever had a girlfriend crying on their couch eating Ben & Jerry’s has wanted to say that to the guy. It felt like a weight off my chest, to get to say that and have that stage to say all those things.”

The Bachelor: Women Tell All airs on Sunday, February 25, at 8 p.m. ET.

With reporting by Emily Marcus.