A clip from an upcoming episode of Keeping Up With The Kardashians shows 18-year-old Kendall Jenner and her big brother Brody bonding at the bar in their swanky Thai resort when a fellow holidaymaker starts to make Kendall feel uncomfortable.

The man can be seen reaching over to Kendall as she stands next to her big brother.

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Kendall makes a mortified gasp and exclaims “excuse me” before rushing over to the other side of her brother.

“That guy just grabbed my a**,” she said.

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The 30-year-old then transformed into protective brother mode, squaring up to the pervy holidaymaker.

"Did you just f_ing touch my sister? Are you f_ing kidding me, bro?” he says, before hitting his sunglasses off his head.

Watch the clip below:

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