Fran doesn't hold back as she opens up about her dislike for Lewis, and also claims that he is "bitter" because she turned him down romantically when they were teenagers.
"If your slagging me off, that's cool," a fuming Fran said in a video posted on the official TOWIE website. "He's just an arrogant a***hole and that's it at the end of the day."
In recent weeks, viewers have seen rising tension between the pair after Lewis declared his feelings for Fran's best mate George Harrison, who is currently dating Tom Pearce.
But after advising George to stay away from Lewis and focus on Tom, Fran soon found herself embroiled in a bitter personal feud with Lewis.
During Sunday's show, Fran confronted Lewis about remarks he made about her "sleeping with half of Essex". After the show, the feud soon spilled over onto Twitter, with Lewis branding Fran a "pug".
"He has no respect for women and that's all I can say," Fran continued. "At the end of the day, he's trying to get with my friend and I'm only trying to guide my friend. He feeds me the same b******t and he's very bitter towards me because I've turned him down ever since the age of 16.
"He's gone bitter with Lauren and George. It just goes to prove my point that he's a compulsive liar. If you're going to slag me off, admit it, that's all. We'll just keep our distance."
Despite her ongoing feud with Lewis, it seems Fran has bigger issues to deal with after learning boyfriend James 'Diags' Bennewith haS naked pictures of his ex on his mobile phone.
Tonight (29 October), viewers will see Fran and Diags' relationship under strain after the shock revelation, leaving fans wondering if they'll be able to beat TOWIE's relationship curse.
The drama continues in The Only Way Is Essex on ITVBe at 10pm on Wednesday 29th October.
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