Demi Lovato has got a new tattoo.

The 20-year-old star celebrated the release of her fourth album 'Demi' by having lyrics from her track 'Warrior' inked onto her back, courtesy of New York-based tattoo artist Bang Bang.

Demi posted a photo of the italic writing, which reads '

now I'm a warrior', on her Twitter account, adding the caption: "Thanks @BangBang! Album release day!!! #DEMI (sic)"

It's been a busy week for Bang Bang as he also tattooed British model Cara Delevigne, inking a lion onto her index finger. His work was recommended to the British model by her best friend Rita Ora and Rihanna who have both gone under his needle.

On the song 'Warrior', Demi - who went to rehab in 2010 to be treated for an eating disorder, self-harm issues and bipolar - sings about having "thicker skin" and having "shame" and "scars" and she has admitted

Demi has 12 other tattoos and admitted she regrets many of them and has even considered having laser treatment to remove them.

She said: "I've thought about it before because, you know, when I get older I don't know if I want to have rock and roll on my middle finger.

"I'm young and I can rock it now and when I get older I can worry about it later."

Speaking of one inking, a tattoo of her friend's lips on her wrist, she added: "It was just a spur of the moment, stupid decision."