A cringe-inducing video has emerged of a woman accidentally filming herself cheating on her 'husband' but tells him that the person she's kissing is her 'brother'.

Rebecca Zemek appeared on Married At First Sight, season eight and was romantically matched with Jake Edwards.

Expert, John Aiken, opens the segment by explaining she'd recently done a 'mercy dash' back to Perth to tend to her sick dog adding that there's something about it that needs 'clarification'.

The room is then shown a video of Rebecca giving an update on her sick dog, saying that she'd checked Jake was okay without her and then cooing over her pet.

Then it seems as if Rebecca believes she's stopped recording as a blurry man approaches her, greets her and the pair are heard to be kissing passionately off camera as the dog whines.

The group looks shocked as the video ends and John asks: "Who was that?"

She looks towards her partner and says: "That was my brother."

Someone off camera can be heard saying: "I don't kiss my brother like that."

"It wasn't, like, sexual," she says indignantly.

Instagram/@backzemek

When questioned if it was her sibling she claims: "Yeh, I was at home.

"It's like you kiss your friends."

Jake asks to watch the video a second time saying: "I know what her brother looks like."

He then asks his partner twice if she's telling the truth, to which she answers 'yes' both times.

When watched a second time the group conclude: "That's a definite pash on the lips. It's literally there."

Another person says: "Bec, are you kidding me? That is not a brother."

The MAFS video, which has been watched 7.8m times since it was uploaded to TikTok yesterday, has received over 4K comments with one saying: "Her actual brother watching and going 'Oh Hell No' that ain't me."

A second said: "I thought she was moaning. it was the dog whining."

While a third was skeptical that the outing was genuine: "Like a single thing happens by accident on that show."

Instagram/@bezenek

Despite her protests, Rebecca later admitted to being unfaithful in an interview with Yahoo! Lifestyle but

insisted it's 'not actually what ended our relationship'.

"I do consider it to an extent cheating. But do I think cheating like that is a hard boundary that should end a relationship? No, I don't," she said.

While they were technically still a couple, she defends herself by saying that she had written 'leave' at the most recent commitment ceremony.

She continues: "I know that my mental health and my state at that time was absolutely shot. And I can only try to forgive myself each day for what I did, because I still hurt Jake and that's the most important part of it to me.

TikTok/@https://www.tiktok.com/@sgkclipsquad

"However, in my mind at the time, I didn't even think I was cheating on Jake. If anyone sees it that way, I'm happy to take it on board, but I know I stuck to my happiness and my truth.

"It's not like I was having a sexual relationship with Jake and had someone on the side. Jake was very aware of how I was feeling about him at that moment."