"You quickly realize that he's searching for what his parents have, his brothers have -- he's the lone wolf in the family. So he is as sincere as any Bachelor or Bachelorette [star] we've ever had," Harrison toldEntertainment Weekly in an interview published Friday.
"He came in so serious to find somebody -- not that the other people aren't -- but you can just tell."
The Bachelor: On the Wings of Love -- the ABC reality dating series' fourteenth installment -- will premiere Monday, January 4 at 8PM ET/PT and follow Pavelka as he whittles down a group of 25 bachelorettes with the goal of finding love.
While Pavelka has previously stated he "didn't promise a ring at the end," Harrison said that the 31-year-old commercial pilot from Dallas, TX felt confident he was going to find his future wife during his The Bachelor journey.
"The first night, he literally looked at me and said, 'My wife's in that room,'" Harrison told EW.
"I thought that's a lot of pressure to put on yourself, but he's that kind of guy. Very focused, very driven, and there's no ifs, ands or buts about why he was there and the show very much took that kind of serious turn."
Harrison said he feels that the pool of suitors "tend to take their cue" from whoever is that season's star, and he added that was no different with Pavelka.
"Jake is actually -- which I think people will learn -- is a very spiritual guy. He is not the Bob Guiney, Andrew Firestone, life-of-the-party [type]. So I think the women really took their cue from him," Harrison told EW.
"It's not that there's not craziness, I just think that it's more on an emotional and psychological level this year. It's not the let's get naked and dive in the hot tub kind of crazy that we've seen in year's past."
Because Pavelka was different than most previousThe Bachelor stars, Harrison said the upcoming installment of the reality dating series also has a different feel.
"There is crazy... But I think it's in a completely different way than our fans are used to," he told EW. "When you see that first cocktail party and you see subsequent dates, you're going to realize this is a completely different show."
While Pavelka previously appeared as one of Jillian Harris' suitors during The Bachelorette's fifth season earlier this year, Harrison said starring in the series "completely changes you forever."
"Until you're really the only guy and all the pressure is on you, you can't describe it and you really can't prepare anybody for it until they walk in those shows. I think it really prepares people and changes you and you know what you're looking for," he told EW.
"It really forces you to do some soul searching, to come to grips with things that maybe you're not too proud of. I think in the end it makes everybody -- regardless of whether you find true love or not -- I think you definitely leave a better person."
Harrison -- who has hosted every installment of both The Bachelor and The Bachelorette -- also reiterated previous claims that the reality series is not scripted but acknowledged it does undergo editing.
"I'll be the first person to tell you we edit the show. We try to throw people off. If you know [Trista Rehn] is going to pick [Ryan Sutter] from Day 1, it would be boring," he explained to EW.
"What we don't mess with is the sincerity. Like with [Ed Swiderski] leaving [during Harris' season of The Bachelorette], we could've talked him back. We could've fixed it. But we have to embrace it. I need to know that when I end up on [The Ellen DeGeneres Show host Ellen DeGeneres'] couch, I can look her in the eye and tell her we didn't lie, cheat, or steal."
"She's half of a relationship. She's not an idiot. But she didn't know what was about to happen. So that was a very genuine moment. In that situation I understand how it looked to America. Like, beautiful proposal, and then we're in a studio and it's all falling apart," he told EW.
"But for us it was a six-month period. I know people think we are so full of s--t, but when I was there [at the proposal] it was as real as it could be."