Could marriage be in the future for Thomas Ravenel and Kathryn Dennis?

While the on-and-off couple is known for the up and down nature of their relationship, Ravenel said he wasn't quite sold on the idea of a future marriage during last night's episode of Watch What Happens Live with host Andy Cohen.

"I don't think so I just think, again, I've said this innumerable times, the age difference is so great," he said on Monday night, via The Daily Dish. "It's like my preacher told me, and he was a sex therapist, 'cause he said, 'Look, things are going great now but in 15 years, you know, how much Viagra am I gonna have to buy?' It's gonna get expensive."

Although Ravenel attempted to downplay his rumored kiss with Dennis during the episode, he admitted to Cohen that there is still something between him and his much younger ex-girlfriend.

"There is, it's palpable," he said.

As for their current relationship, Ravenel admitted that things between him and Dennis, the mother of his two children, are much better than they once were.

"My relationship with Kathryn has gotten a lot better," he said. "We communicate. We're civil. We're cordial to each other. There's no animosity."

In other Kathryn Dennis news, the reality star recently moved back in with her parents.

"Well I'm back home in Moncks Corner. I'm living with my mother, my father. For personal reasons, but it's been wonderful," she said during an interview with The Daily Dish. "It's my safe haven. It's private. It's out in the woods, in the country. I enjoy it."

To see more of Kathryn Dennis and Thomas Ravenel, tune into new episodes of Southern Charm Season 4 on Monday nights at 9 p.m. on Bravo TV and check out more from Ravenel's Watch What Happens Live appearance below.