Katy Perry and Ruby Rose Gatecrash Melbourne High School formal

 

Katy Perry and Ruby Rose Gatecrash Melbourne High School formal

 

Katy Perry added some serious star power to the Melbourne High School formal at the Grand Hyatt on Friday night, crashing the event with her Aussie gal pal Ruby Rose.

 

The dynamic duo were out on the town and decided to make a surprise appearance at the event, slipping in to the hotel's ballroom through a back door around 11pm, just as her hit single California Gurls began to play.

 

Perry grabbed a microphone and waded through the sea of students on the dancefloor before she began singing along to her track.

 

Perry did not linger long after her song finished, but posed for plenty of pics before dashing out the door with Rose.

 

The pair continued their big night on the town, having a good time at the Spice Market nightclub at the Grand Hyatt and then Boutique nightclub in Prahran.

Perry left Melbourne yesterday and is now in Tokyo.

 

Katy Perry was in Melbourne to performed at the Regent Plaza Ballroom for the Debit Mastercard Priceless Music Series.

 

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