A scorned girlfriend was left furious when she witnessed her long-term boyfriend telling another woman that she was his sister as he flirted with her on a reality TV show.

A man named Patrick, from the US, thought he was being filmed for a game show but his behaviour was actually being exposed on To Catch a Cheater, according to the Daily Mail.

His girlfriend of two years watched in horror as he flirted with the "game show hostess", gave her a massage, exchanged Instagram usernames and boldly claimed his girlfriend in his social media pictures was actually his sister.

Patrick's girlfriend watched from behind the scenes, dubbing him a "f****** moron."


She then stormed onto the set and screamed: "I'm your sister?! You swapped Instagrams with her, you're putting your hands all over her."

Once he had been caught, Patrick claimed he thought he was at an audition for a game show.

However, his girlfriend - who duly informed him she'd set the whole thing up to expose him - wasn't buying his story.

She screamed: "All the c**** that I've done for you, you've been living in my f*****g house.

"He doesn't have a f****** job. You don't have a job, how do you eat? Me!"

A guilty Patrick then boldly claimed his girlfriend was "embarrassing herself" and even tried his luck on the hostess after his girlfriend had left the set.