The raunchy clip, which is believed that have been filmed at a branch in Italy, has been viewed over 600,000 times after being posted on Instagram.
Shot by a fellow customer, the video shows the man standing close behind his girlfriend.
The fast-food loving lady then pulls her figure-hugging dress up towards her waist – exposing her bare bottom.
As the burgers and fries are delivered, the pair begin rubbing up against each other.
Despite the couple’s high-jinks, the branch’s staff do not appear to notice and continue to serve them.