Kevin Hart's sex tape partner, Montia Sabbag, doesn't look the least bit concerned about the extortion investigation ... in fact, she's taking a totally casual approach as she kicks it in L.A.

Montia was at a home in the L.A. area Wednesday just hours after she held a news conference with celebrity attorney Lisa Bloom to publicly deny any wrongdoing, and declare she was also victimized by the sex tape recording. 

She was rocking a far more casual look -- a midriff-baring pink sweatsuit -- than the all-business blouse she wore at the newser. As for her weekend in Las Vegas with Kevin ... seems mum's the word, at least when her attorney isn't present.

CAREFREE LIVIN'
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CAREFREE LIVIN'
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