The 38-year-old 'Bodies' singer, who welcomed baby daughter Teddy into the world with wife Ayda Fields last month, wore a suit and floral print shoes as he cavorted with the clothes-less girls.
Williams sang new single 'Candy' from upcoming album Take the Crown, set for release in November.
The star was also in Milan to launch his menswear fashion collection Farrell at luxury department store Coin.
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