LONDON — Buying clothes for family members989? ??? ??? ??something of a minefield.

Not only do you have to make sure the size is right, but you've also got to be 100% certain they're actually going to likethe damn thing.

It's also a good idea to double-check the pattern.

At a glance, the Vivienne Westwood t-shirt (below) that 18-year-old Twitter user Katie received from her mum looks innocent enough: white with a thin gold pattern and a little logo on the front.

On closer inspection, though...

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Yep, that's essentially a mass orgy on a t-shirt.

At the time of writing, Katie's tweet has been shared around 3,500 times. People can't seem to get enough of it.

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Katie told Mashableshe's since told her mum about the tweet going viral.

"She's finding it hilarious but is just as confused as I am, with why it's getting so much attention," she said.

"I think she secretly knew and was just trying to wind me up but every time she looks at the shirt she just laughs hysterically."

As for the t-shirt itself? Well, Katie has decided to embrace it.

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