The 'Bachelor in Paradise' alum does, however, think Underwood ends his season happy.
Tia Booth doesn't think her ex, Colton Underwood, has lost his virginity yet -- and she jokes it's possible he never will!
ET's Lauren Zima spoke with the Bachelor in Paradise star and her new boyfriend, Cory Cooper, at the Los Angeles premiere of Isn't It Romantic on Monday, where she opened up about her ex's season of The Bachelor.
"No, I don't think he does [lose his virginity on the show]," she said. "Because I think he's gonna wait for f**king ever!"
In all seriousness, Booth confessed that she hasn't actually been watching Underwood find love on TV; she's just been keeping up with the highlights on Twitter.
"He makes out a lot. They don't talk a lot on dates, they just make out a lot," the brunette beauty hilariously observed. "[But] I think it's gonna end well, I really do."
Booth -- who appeared in a promo for Isn't It Romantic during Monday's episode of The Bachelor -- said that she's kept in touch with Underwood, but that he's been "pretty tight-lipped" about how his season ends up. "I think [his final pick is] gonna be blonde, early twenties," she cracked. "I do [think he'll end up with someone]. I don't think he'd do this whole thing if he wasn't serious about it."
Fans watching this week's episode saw a dramatic promo teasing that Underwood's famous fence jump is almost here. The 27-year-old former football player previously told ET that the move was followed by him quitting the show.
"He actually called me after filming, [and said], 'I wanted to be honest and genuine throughout. I quit at one point, tried to quit, came back.' He felt like it was wrong, it would be a disservice to the girls. So, that's why I think he's serious about this and he really did it to find a wife," Booth expressed.
All seems well between the exes, as Booth revealed that Underwood wants to meet her new man, Cooper. "He wants to meet Cory, but Cory's like, 'Eh, that's your ex, that's kind of strange,'" she admitted. Cooper, however, couldn't be more supportive of his girlfriend.
"I did not watch her on TV or know who she was. I was actually set up through a coworker of mine, and we just get along," he told ET. "We're from the country and we just really bond."
"We're long distance, so when we're together, it's really good," Booth sweetly shared.
Isn't It Romantic hits theaters on Wednesday. The Bachelor airs Mondays at 8 p.m. ET/PT on ABC -- join ET's Bachelor Nation Facebook group here.
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