I thought that "Mother Fucker" was just a derogatory term.

It’s no secret some guys are attracted to women who look like their moms. But one pair is taking it way too far.

Kim West, 51, and her son Ben Ford, 32, are in a sexual relationship. In a cover story for the UK tabloid New Day, the couple say they’ve been in a relationship for two years, plan to marry, and have an “incredible” sex life. Yeah…

Let’s back up a sec: According to reports, Kim gave up Ben for adoption when he was a week old. They were reunited in 2013, when he sent her a letter out of the blue. It started out with phone calls, but Kim says she realized she was attracted to Ben and started having “sexy dreams” about him. They finally met up at a hotel, shared a bottle of Champagne, and had their first kiss…and things progressed from there.

Ben was married to someone at the time but ended up leaving her so that he could be in a relationship with his mom.

According to the couple, they’re experiencing “Genetic Sexual Attraction,” a term used for relatives who are sexually attracted to each other after meeting as adults. “This is not incest, it is GSA,” Kim tells New Day. “We are like peas in a pod and meant to be together.”

What the what? While Kim and Ben are holding firm to their claim that they’re simply victims of GSA, clinical psychologist John Mayer, Ph.D., says it’s not really a thing. “My professional opinion is that GSA is an excuse to give these people permission to break social norms,” he says.

Mayer points out that incest is one of the only social taboos that exists in every society ever—and engaging in incest has one of the strongest social stigmas known to man—for good reason. “There is no justification for this,” says Mayer.

Mayer even suggests that Ben and Kim may be sociopaths, or that they break social rules without remorse.

New York City sex therapist Ian Kerner, Ph.D., has his doubts, too, pointing out that GSA has never been studied. “While I wouldn’t necessarily discount it, I think that our mating systems tend to seek out genetic difference more than similarity,” he says. “In the case of incest or romantic love between family members, I think you have to look at it case by case instead of generalizing it as a disorder or genetic condition.”

Unfortunately, this isn’t the first time this has happened. New York Magazine did a story in 2015 called “What It’s Like to Date Your Dad” that featured an 18-year-old girl who lost her virginity to her father after being estranged from him for 12 years. The couple says they have an immediate bond due to GSA and plan to get married and have babies.

But Kim swears it’s for real. “When you’re hit by a love so consuming you are willing to give up everything for it, you have to fight for it,” she says. “It’s a once in a lifetime chance and something Ben and I are not willing to walk away from.”