Chloe, 22, and Marc, 44, were thought to have broken up earlier this year and haven't been pictured together for some time, although it seems that their romance is well and truly on track judging by these holiday snaps.
The Topshop heiress couldn't keep her hands off Marc during their sunny getaway and was spotted smiling, laughing and gazing at her beau while they strolled along the sea to exclusive Club 55.
Chloe embraced the warm weather by sporting a white swimsuit, which she teamed with a stylish black kaftan, white sandals and a straw hat.
Meanwhile, Marc - who has two children with ex-wife Jennifer Lopez - also wore white for their outing in a shirt that matched his girlfriend's bathing costume and a pair of khaki shorts.
The couple were joined by Chloe's parents, retail giant Sir Philip Green and Tina Green, who had no doubt given Marc their seal of approval since he was seen lapping up their luxurious holiday perks, which included a boat ride on the French Riviera.
Chloe and Marc's relationship was thought to have ended on more than one occasion this year, with Chloe even being rumoured to have embarked on a romance with Chris Brown.
However the couple keep proving their doubters wrong with loved up pictures of them together, including one Chloe shared of Marc kissing her back in April.
The petite brunette has even formed a bond with Marc's twins, Emme and Max, as she spent the day with them at Disneyland in California at the beginning of the year.
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