Tattoo.

Someone apparently needed a tattoo like a hole in the head - and got both. A tattoo artist from Utah posted an image on social media showing an optical illusion which makes it look as if one of his clients has a hole in the back of his head. The tattoo was the work of Matt Pehrson (right), an artist who runs the Zion Tattoo Company based in St. George, Utah. 'Did a crazy thing on my friend Ryan today...' Pehrson wrote on his Instagram account. Pehrson drew several thick lines on Ryan's bald head that turn inwards to the back of his skull. With clever shading, the artist created an eye-catching illusion making it look like Ryan had a massive hole in his skull.

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