Fresh from her weekend of partying and performing at Glastonbury Festival, Lily swapped her wellies for stilettos for the showbiz event.
And making sure to cause quite a stir, the 29-year-old couldn't help but give us a glimpse of her pert backside.
Sporting a little black mini dress, Lily glammed up for the evening and, although her dress was demure at the front, it's low cut, string back sure did flash the flesh.
But not quite taking things as far as Rihanna (remember that boob flashing see through dress?) Lily covered up her behind with black underwear.
The 'Not Fair' singer pulled out all the fashionista stops accessorising with a gorgeous pair of Louboutin heels and a sequinned Chanel bag.
It seems Lily, since showing off her new red and black hair do, has given her locks another burst of colour, lightening her ends and adding a purple and pink hue around the roots of her hair.
If anyone can pull of a multi-colour do, then it sure is Lily.
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