It started when the woman let her dog take a dump on the terminal floor.
Los Angeles International Airport is a really busy place - but according to Steve Hofstetter, seeing a fellow passenger simply leave it there for someone else to clean up was enough to stop people in their tracks.
The comedian took revenge on behalf of the other passengers, sharing his story on Facebook, although he admits he "may have gone too far".
Here some excerpts from the post - you be the judge.
Hofstetter first became irked when a gentleman tried to get the woman's attention.
"Excuse me, miss?" he said politely. "Your dog?"
According to the post, the women merely rolled her eyes and went back to the loud conversation she was having over the phone.
"Some people," she bellowed to her face-time companion with no hint of irony, "are just so damned rude."
When she started to walk away, another woman tried to stop her.
"You're not going to clean that up?" she asked in a shocked tone of voice.
"They have people for that," the offender replied, disappearing into the crowd.
Hofstetter claims he stood near the steaming pile and warned people to walk around it while someone else got a maintenance worker's attention.
It's actually not uncommon for pets to fly with their owners in the United States, and a number of airports have facilities for passengers travelling with animals.
A therapy duck called Daniel won over the internet in October, while other passengers have spied pigs, a kangaroo and even a pony spotted comforting their owners on board.
"I have nothing against people flying with their dogs, I do it often. But it is a privilege I take seriously. My dog is well-trained and behaves better than most people. He certainly behaves better than that asshole [sic]," he ranted.
"Speaking of assholes [sic], there is a pet relief area inside LAX, past security, just two gates away from where The Party Pooper let her dog go to town. It didn't matter - she was the type of person to litter three feet from an empty garbage can."
He was horrified to find her sitting at his gate, preparing to take the same flight to Tokyo, listening to music with no headphones.
"We were so shocked anyone could be that horrible," he wrote.
"Everyone else tried to ignore her, sitting as far away from her as they could. I am not everyone else. I sat down right next to the horrible woman," he wrote.
"Are you going to London on business?"
"I'm going to Tokyo," she responded gruffly.
"Then you better hurry. That flight got moved to gate 53C. This is the flight to London."
He said he just wanted to give her a little moment of panic, as payback for how terribly she was treating everyone around her.
"I didn't predict what would happen next," he wrote.
"She grabbed her bags and her dog in a huff, and stormed out of the gate without even checking. She was so self-involved, she didn't notice that the monitor at our gate still said Tokyo and almost everyone at the gate was Japanese."
He said he's not sure if she made the flight or not, but he didn't see her board and he couldn't hear her dog.
"Maybe she can re-book on another airline. I hear they have people for that."