Bendjima, 24, and 18-year-old Richie were spotted at Liquid Juice Bar in Los Angeles on Aug. 17. The two were laughing and seemed especially cozy with each other.
Kardashian, 38, at first tried to brush off Benjima's flirty date with Richie, but she quickly melted down and she's now "absolutely furious," an insider exclusively revealed to RadarOnline.com.
"She ripped into Younes demanding answers and accusing him of making her look like a fool," the insider dished of the couple, who met last fall at Paris Fashion Week.
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"This is history repeating itself all over again as far as Kourt's concerned," noted the insider of the reality star, who dealt with her fair share of deception while with sketchy Scott Disick.
"If Younes thinks he can turn into another Scott he's wrong," blasted the insider.
However, conceded the insider, Kardashian may be overreacting: "Younes was taken aback, because he and Sofia have been friends for a while and he insists they're more like brother than sister."
Added the insider, "He accepted Kourtney's new rule that he needs to reign in the flirty body language around other girls and inform her in advance before anything like this incident happens ever again."
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