'90 Day Fiancé': Andrei Says He's Going to 'Expose' Elizabeth's Siblings (Exclusive)

Andrei tells ET he's got some serious dirt on Elizabeth's siblings.

When it comes to 90 Day Fiancé star Andrei's explosive relationship with his in-laws, there's plenty more surprises to come on this season of 90 Day Fiancé: Happily Ever After?. ET spoke to both Andrei and his wife, Elizabeth, about all the drama they're having with her siblings, and Andrei said that secrets he's exposed about them will come to light soon.

So far this season, Andrei's plans to work with his father-in-law in Chuck's property management business have gone badly. Both Elizabeth's brother, Charlie, and one of her sisters, Becky, have butted heads with Andrei, accusing him of attempting to take their sales and not wanting to work his way up. Elizabeth's siblings were also outraged over Andrei's earlier request for Chuck to loan him $100,000 to start his own real estate business when he just got his real estate license.

Andrei said that when it comes to Elizabeth's siblings, he's not going to back down. And he's clearly not over her family digging up information on him prior to his second wedding to Elizabeth in Moldova.

"Maybe I'm prideful but I don't think that's a bad trait to have," he tells ET's Melicia Johnson. "As I've said before, I'm up for a fight. ... I'm gonna dig in your past like you dig into mine, I already know a lot of stuff and, you know, there's a lot of surprises coming up over here in the upcoming episodes."

"It's gonna get harsh," he continues with a big smile. "Right now, it's going to get fiery."

Andrei said he did an "investigation" on what he discovered while working with Chuck and more of Elizabeth's family.

"The other siblings are going to get a little bit exposed," he says. "They stepped on my tail now they have to ... they're going to get the bear."

Meanwhile, Elizabeth told ET she didn't feel bad at all about her husband exposing her siblings.

"I mean, if you walked into it, that's on you," she says. "They did a lot of things to piss me off and at this point, I'm just kind of like, you guys are asking for it because he told them, 'I'm warning you.'"

Andrei also explained why he didn't feel bad about asking Chuck for a $100,000 loan since he said his father-in-law has helped out all of Elizabeth's siblings financially.

"Everybody did that to Chuck," he says. "Everybody got the same treatment, like, he's been helping his sons and his daughters in all kinds of ways, giving them money ... they just don't want to share. The thing is, they're selfish. The fact is they all have their share of the pie over here ... and now that I'm asking for something in the same manner, they're like, going nuts, because they're thinking, like...  maybe he's going to take over, which ultimately, will probably happen."

As for why he didn't look for a job outside of the family business given that he has a history of not getting along with his in-laws, Andrei said that was never really an option given the opportunity he has with Chuck's business.

"I'm going to use the resources over here, it's kind of hard at this moment in time, like, immigration and stuff like this, but at the same time there's millions over here circling around, like, why not just dip my hands in it?" he asked. "If it's money talks, I'm up here for the fight. If this is what it takes, I'm going to fight for it."

As for where Andrei's relationships with Elizabeth's siblings stand today, he said that he hasn't even spoken to a few of them in a year and that when he sees them he doesn't even say hi.

"I am there because [Elizabeth] asked me," he says of being present for family functions. "It's purely because we have something in common, that's my wife and it's her sisters and stuff. But soon enough, we're going to settle that down too. We're going to make it happen."

90 Day Fiancé: Happily Ever After? airs Sundays at 8 p.m. ET/PT on TLC.