Katy Perry vamps it up in thigh high boots while Anna Kendrick dresses down in jeans as they party in London with John Mayer

Someone didn’t get the dress code memo! Katy Perry and Anna Kendrick partied together at Shoreditch House in London on Sunday and displayed their very different stylesDemure: Anna was positively demure in comparison to Katy who was dressed up for a night of clubbing in a black corset, sparkly skirt and thigh high bootsDate night: Katy’s boyfriend John Mayer was spotted leaving the club behind her with some friendsGlum: While Katy couldn’t stop smiling as she left the club, Anna appeared more downbeatExcited: Earlier Katy left the X Factor studios for her night of clubbing with Anna and John, looking delighted with how her performance had goneVamping it up: Katy added bright red lipstick and thigh high boots to her outfit for her night out in LondonSupportive: John celebrated Katy’s performance with her in London on Sunday nightEnjoying himself: John looked like he had enjoyed himself at Shoreditch House in London on SundayWhat a pro: While Katy greeted fans, John left the club with Frank OceanCoy: Katy and John made sure they weren’t photographed together as they left the club in the early hours of the morningSexy: No doubt John will have been impressed by Katy’s daring outfitMeeting the fans: Katy hugged a fan as she left Shoreditch House following a night of partying with John and AnnaWorse for wear or just sleepy? John looked like he had enjoyed his night as he left the clubOn top of the world: Katy’s huge smile didn’t leave her face all night following her successful performance on The X FactorLooking grrr-eat: Katy Perry wore a sexy tigress outfit as she took to the stage on Sunday night to perform Roar on The X Factor‘I feel grrr-eat!’ Asked how she felt about the performance, Katy made a humorous reference to her tiger outfit