Kourtney Kardashian flashes her booty in thong bikini while on vacation: Pics!

Showing off her assets! Kourtney Kardashian is loving her vacation life, spending time with pals and her kiddos in Nantucket, Massachusetts.

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On Monday, she shared several beach shots on Instagram of herself in a maroon thong bikini.

"Yesterday when we had the beach to ourselves," the 38-year-old captioned a shot of herself sitting on the beach with pals Allie Rizzo and Stephanie McDonough.

See photos from Kourtney Kardashian's Nantucket vacation:

She also showed off her toned booty while drinking wine and looking out at the ocean.

"All week," she wrote.

The mother of three also gave fans a look at the front of her suit in another shot on the shore, writing, "She's not a local."

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Kourtney's been having quite the luxurious summer, traveling to the French Riviera with her new boyfriend, Younes Bendjima, earlier this month.

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