Unsworth, who adapted the Animals screenplay from her book of the same name, has said that porn is the reason why it was so important to make the scene as excruciating as possible.

“I wanted to make the sex scenes really awkward and excruciating. Especially that one, it’s like a porno thing that has happened to so many of my friends,” Unsworth said at a screening of the film, according the Independent.ie.

“So I put it in the film to ask: what is going on here?”

She elaborated on the scene, adding: “That is not good for the woman at all. She will get nothing out of that, so it felt really good to put that in there to liberate us from this ridiculous action.

“It’s like a record scratching, it’s not working. Stupid porno stuff. Stop.”

Even actor Dermot Murphy - who played Marty - said the scene “was hard to watch”.

Animals: why that excruciating oral sex scene is so important