Girl’s nude illusion pic becomes Internet sensation.

A picture giving a nude illusion of a girl is going viral around the world.

At the first glance, the photo seems to show a naked girl posing behind a pal — but after looking at the saucy snap carefully it emerges that the photo is actually an optical illusion created by her friend`s bare arm, reports the Sun.

The embarrassing shot has become an Internet sensation around the world.

It appears in an email with the subject "The awkward moment", with the line: "When your friend`s fat arm makes you look naked."