Miley Cyrus Gets Cozy With Costar BF After Concert

Miley's summer fling and Last Song star Liam Hemsworth stays for the show, and the afterparty

It looks like Miley Cyrus' on-set romance with her Last Song costar Liam Hemsworth wasn't just a summer fling.

The Australian hottie was in the audience for Miley's sold-out show at the Staples Center last night, and he wasn't just there as a fan like Ashley Tisdale and Miranda Cosgrove.

According to a source, Liam is officially her boyfriend and the couple have been dating for more than three months.

And being the savvy marketer she is, Miley's already found a way to incorporate her new man into her show...

Before she performed a song from their movie, Miley gushed about how life really can imitate art as a makeout montage of them played behind her.

The twosome didn't try to hide their affection later at her private afterparty at Katsuya, where they were "lovey-dovey."

As for her ex-boyfriend and underwear model extraordinaire Justin Gaston, he was busy watching another girl work the crowd across town.

Miley's best friend, Mandy Jiroux, was performing with her group The Beach Girl5 at Upper Manhattan, and Justin was in the audience. 

When asked why he chose Mandy's concert over his ex's, Justin told E! News  he "didn't even know Miley's tour was in town."

Whatever you say, Justin. We're giving props to Miley for upgrading to another hottie with an Aussie accent. Well played, Miley, well played.