Optical illusion of sitting women sparks debate as legs don't 'add up'

An optical illusion has left internet users baffled as it shows six women but only five pairs of legs, and no one knows what's going on.

In the image, five women are sitting on a bench in a bar of some sort, and another woman is perched on the arm on the right-hand side.

It appears there is a set of legs missing somewhere, and a Reddit user has shared the image online to try and get answers.