Tweeting from the tattoo parlour about her Tupac Shakur inspired tattoo, she said: "All these bitches screaming that 2pac back #THUGLIFE".
She included this photo of her latest body art.
During her 'tat night' she also posted a snap of her tattoo artist appearing to ink something onto her back or arse while she posed with a bottle of beer.
'THUG LIFE' is Rihanna's fifth tattoo. She also has a handgun on her side and 'Always a failure, Always a lesson' on her chest.