She and Max first got together while starring on the first series of Love Island last summer, but they're romance only lasted for six weeks following the show. Fans will know that things ended quite bitterly between the pair, and it seems like Jess and Max have no intention of becoming pals just yet.
Earlier today, he said he made "a big mistake" when it came to Jess and now she has had her say...
She tweeted: "Is he still going on jeeeez the guy makes my skin crawl have a day off #SleezeBag."
Jess added an emoji of a face feeling sick and liked several tweets that fans had sent her in support. One read: "He makes my skin crawl too." While another said: "He don't half go on about you considering you were a "big mistake" pr*t."
Fans will remember that Max and Jess' relationship was never plain sailing. Max set his sights on Jess shortly after arriving late to the villa, but it soon became clear he had turned his attentions to Naomi Ball instead.
She had been dating Josh Ritchie at the time, but split with him to pursue things with Max. Although, she got the boot just a couple of days after, and Max then decided to rekindle things with Jess, telling her: "I've obviously f*cked up. We do get on well, we have a laugh, I kind of shot myself in the foot when I said I want to choose Naomi...
"I've had the opportunity tonight to meet new people and hand on heart, if you walked through that door I would 100% pick you," he said.
The pair's reunion saw them eventually go on to win the show, but their relationship broke down back in the UK - and Max and Jess haven't seen eye-to-eye since.
Their latest digs at each other were sparked by a video ITV2 had shared on Twitter to promote Love Island's new series.
It was a video advising Love Island's new contestants on lessons in love, they told them to always go with their head (not their bits!) and used Max as an example.
ITV2's Twitter account shared a video of Max debating whether to go for Naomi or Jess. He says: ""Do I now carry on with Jess, get my end away? Or do I start with something Naomi and not have sex? It's a genuine penis/head dilemma."
Max re-tweeted the video, adding that it was a "hard decision."
When Naomi called him out for being a 'liar', Max told her: "I made a big mistake."
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