was front row and centre at the Yves Saint-Laurent fashion show in Paris today (March 5).
The perky pop star jazzed up her YSL frock with leather boots and a leather jacket as she took in the show alongside her Entourage.
Also in attendance? Salma Hayek, Alicia Keys
and actress Rosario Dawson
Meanwhile, Katy insists her new song, Part of Me
, isn't about her romance with ex-husband Russell Brand
The song is full of jabs and barbs ...