Customers of a San Francisco robotaxi service have lately been using the driverless cars to have sex while they travel to their destinations, according to a report.

Several clients of the Cruise robotaxi startup told The San Francisco Standard that they have had several sexual experiences while hitching a ride in the tech company’s autonomous vehicles that have grown increasingly popular in the City by the Bay.

“It was really funny because [the Cruise] got quite hot and fogged up to the point that the windshield was completely fogged over — in any other context, in any other vehicle, that would be an actual problem,” a Cruise rider, Alex, told the Standard.

Alex, a man in his 30s, told the publication that he estimates he has performed at least six separate sex acts spread out over the course of three different rides in a Cruise car.

He said that the romps ranged from make-out sessions to “full-on [sex], no boundaries activities.”

“I mean, there’s no one to tell you, ‘You can’t do that,’” he told the Standard.

“It gets to the point where you’re more and more and more comfortable, and if you’re with someone, like a more serious partner, it can escalate to other activities.”

Alex added: “It seems like I’m a trailblazer.”

“It’s also fun to realize that this is like the first place you can do this in the country — the first [autonomous vehicles] that exist,” he said.

The Standard also quoted Alex’s partner, Megan, a woman in her 20s, who described her first experience in which her robotaxi ride escalated into something more.

“We got in and just got straight to it, making out,” said Megan, who got into the Cruise car wearing nothing but a robe.

“One thing led to another, and he made sure that I was taken care of, if you will,” she told the Standard.

“I was like, ‘I have no underwear on, and I am ready to go in this kimono’,” she said.

“And I was using his slippers that were like five sizes too big.”

The Standard reported that at least four people who have used Cruise self-driving taxis in recent months have engaged in sexual behavior during their rides.

The publication did not quote anyone who did the same while using Cruise’s rival, the Alphabet-owned startup Waymo.

The Post has sought comment from both Cruise and Waymo.

California regulators last week gave the green light to allow Waymo and General Motors subsidiary Cruise to deploy more autonomous taxis throughout San Francisco and to charge riders at all times — a major win for the self-driving industry as it looks to take on ride share giants Uber and Lyft.

The California Public Utilities Commission on Thursday sided with the companies in the face of vigorous opposition from some residents and city agencies.

Commissioners heard more than six hours of public comment from residents and special interest groups supporting or opposing the measure that would expand paid autonomous vehicle service.

Cruise and Waymo now have permission to begin citywide paid taxi service at all hours of the day and have said they plan to deploy more cars as a result.

They collectively have more than 500 autonomous vehicles already in operation.

Cruise and Waymo have been running experimental services limited by times and geographic areas within San Francisco.

Neither indicated on Thursday how soon they may move to make round-the-clock taxi service a reality, but they promised to do so soon in promotional emails after the vote.

The move is a critical step forward in regulating the robot cars, which Waymo, Cruise and others have been systematically rolling out in cities and states around the nation.

With Post wires