This was one sickening public display of affection!

A British photographer captured a canoodling couple on the platform of London’s Underground, as a woman heaves in the background, exposing her bum in the process.

The scene is rendered even more surreal by a security guard who throws a furtive glance at the lovebirds as he raises his walkie-talkie to call for backup at the Embankment station.

“Cleanup on platform two — we have human spillage,” he then says, Caters News reports.

The shutterbug, Paul Coomber, had spent the evening taking pictures at Covent Garden and at the River Thames before taking the quirky photo in the Tube station — calling it “Mind the Gap.”

“It was too good an opportunity to miss because I think it tells a story about London,” said Coomber, 56, a retail worker. “There’s the concern in the eyes of the platform guard, who wishes he was anywhere except work and probably had to deal with the mess afterwards. There’s this young, professional-looking couple embracing each other, clearly doing their best to ignore her and wanting their train to hurry up and arrive.”

And what about the retching woman?

“I didn’t see her face properly, but she looked to be in her 20s. I only took one picture and then the guard moved in to shield her and protect her modesty,” he said. “She was clearly a bit worse for wear and doubled over as if she was about to throw up.”

Coomber’s train pulled up moments later and he returned to his Croydon home in south London — thinking he had just captured his best photo of the year.

“Sometimes you spend all night fiddling with the right settings taking hours to get a good picture, but with this one I just had the camera around my neck and quickly took the cap off the lens,” he said.

Alcohol was banned from London’s subways and buses in 2008. PDAs are still legal.