is taking mirror selfies to a whole new level, because the "Malibu" singer's latest selfie is NSFW.

On Monday night, the singer posted a belfie (butt selfie) to her Instagram story, wearing a lace, electric blue matching thong and bra set that showed off her arm and lower back tats. The "Midnight Sky" singer showed off her behind in her larger mirror, as well as a close up angle in her smaller iron mirror which is sitting atop a Gucci plate.