We always had natural beauty Kendall Jenner down as the shy and retiring type.

But it appears that the Keeping Up With The Kardashians star is far from it, particularly after sharing this NSFW picture on social media.

To celebrate reaching a whopping 40 million Instagram followers, the flawless model decided to flash her nipple in a racy black and white shot.

It’s probably not how we’d decide to celebrate, but then again we don’t have 40 million Instagram followers.

Kendall, who celebrated turning 20 earlier this week , can be seen beaming into camera as she pulls down her black vest to reveal her cleavage.

Kendall, Kylie, Khloe and Kim are some of the most followed stars in the world

“My favorite photo for all 40 million of you. Genuine happiness,” she captioned the sexy snap.

Kendall reached the milestone a few months after her little sister Kylie hit the 30 million mark and celebrated by sharing an equally smouldering selfie as she showed off her award-winning pout.

It means Kim, Kylie, Kendall and Khloe all fall into the top 10 most followed people on Instagram in the world.

Other celebrities to feature in the top 10 include Nicki Minaj, Justin Bieber, Ariana Grande, Beyonce, Selena Gomez and Taylor Swift.

Kendall Jenner’s 20th birthday party

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