And, rather unsurprisingly, the actress looks totally mesmerising as she smoulders in the scent's new campaign pictures!
The Transformers star, who is expecting her second child with hubby Brian Austin Green, looks every inch the bronzed goddess in a metallic leopard print top.
She oozes glamour with sultry smoky peepers and bold brows, whilst wrapping an arm around Brazilian model Marlon Teixeira (who looked equally as gorgeous!)
In another snap, Megan is pictured wearing an exotic plunging maxi frock, flaunting killer contoured cheekbones and a nude glossy pout.
The 27-year-old follows in the footsteps of Olivia Wilde, who is the face of the Avon Armour fragrance, and Alesha Dixon, who is the brand's Beauty and Empowerment Ambassador.
Speaking about her new campaign, Megan said: "When Avon approached me to be the face of Instinct, I was thrilled about the opportunity to represent these fragrances.
"I'm so excited to be a part of this brand I've always loved and respected."
Laura Clarke, Avon's European Fragrance Brand Manager, adds: "When we developed Avon Instinct, we were looking for someone who could portray the essence of a wildly alluring fragrance.
"No one evokes magnetic attraction better than Megan - men and women alike see her as a bold, captivating beauty. She's the perfect face for a scent that's intensely alluring."
The new fragrance, priced at £15 for 50ml, launches mid September at www.avonshop.co.uk.
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