A fairytale romance fit for a fairytale premiere!

Kristen Stewart didn't have to attend the London premiere Monday of her new film Snow White and the Huntsman alone. Her Twilight costar and real-life boyfriend, Robert Pattinson, secretly attended the premiere in his hometown at Empire Cinema London.

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"Rob was Kristen's date," a source tells Us Weekly. Stewart, who plays Snow White, presented the film with the cast on stage while Pattinson watched from the audience.

"Rob was cheering and clapping for Kristen as they walked off stage," the source adds. "He looked proud of his girlfriend." 

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After the premiere, the cast attended Ciroc Ultra Premium Vodka's official after party at the Royal Courts of Justice. Stewart, 22, changed out of her black lace Marchesa gown into a leather jacket and jeans. Pattinson, who celebrated his 26th birthday Sunday, also dressed casually in his trademark baseball cap.

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"Rob met Kristen there," a partygoer tells Us. "They stayed together in the VIP area all night and looked really cozy. They made sure no one saw them or photographed them."

But they weren't alone! Pattinson also brought his family to the party to support his Snow White.

This article originally appeared on Usmagazine.com: Kristen Stewart, Robert Pattinson Get "Cozy" at Snow White After Party