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They make the most adorable couple!

Kate Hudson and fiance Matt Bellamy hit the Warner afterparty following the Brit Awards last night, and the actress held on tight to her man as they arrived at the Savoy Hotel for the bash.

Earlier in the evening, Bellamy's band Muse performed at the show, but it was the bubbly blonde entertaining the crowd in the wee hours! The A-list star was jumping on couches and dancing to the music when she wasn't stealing smooches from her sweetie, and she even tried to get away with some bad girl behavior by smoking a cigarette indoors!

"Someone asked her to put it out and she didn't mind. She put it in an empty bottle on the table and apologized. She was really happy, dancing on the chair and Matt was pouring her drinks," a source told Us Weekly.

Sons Ryder and Bingham must have been home with a babysitter so their folks could cut loose on date night!