But going topless to sell a pair of shoes is another story.
But the advertising department for Spanish brand XTi obviously know that sex sells, and got Irina Shayk to do just that.
Want to buy these? Irina Shayk promoted Spanish shoe brand XTi by posing topless and covering her modesty with flip flops
In another publicity short for the brand, she can be seen kneeling on a chair, wearing a tiny pair of denim cut-offs and a short-sleeved shirt tied above the waist to reveal her trim stomach.
The model has been dating Portuguese football player Cristiano Ronaldo, also 26, since early 2010.
In February last year Irina and Ronaldo were reported to be engaged after he apparently jetted from Spain to New York to propose to the Russian beauty on Valentine's Day.
This year, speaking to the NY Post, Irina dished out some advice for women celebrating Valentine's Day.
What about these ones? Irina poses provocatively in a different pair of shoes
The confident model said: 'You just have to be yourself to flirt and be beautiful and sexy. You don’t need to have long legs and big lips and beautiful hair and makeup. Just be a normal person.'
That's easy for her to say!
Real Madrid star Ronaldo is already father to a baby boy. He became a father on June 17 when a mystery woman gave birth to Cristiano Ronaldo Jr.
His mother Dolores is helping raise the baby between Madrid and Portugal. The identity of the baby's mother has never been revealed.