Article continues below advertisementHailey Bieber is a mom off duty.The model, 28, bared her backside in lacy lingerie on the streets of Paris, France, on Monday, September 29.Bieber turned around and exposed her butt cheeks in baby yellow intimates, paired with sheer tights and black high boots.Article continues below advertisementSource: @haileybieber/InstagramHailey Bieber posed in revealing lingerie.In the series of provocative snapshots, she caressed herself, placed a hand on her assets and slipped the straps of her one-piece off her shoulders.