|Proud Gaga ... singer plants a kiss on Taylor's cheek|
The singer played supportive girlfriend at a premiere party for Taylor's new show Chicago Fire.
But she managed to steal the limelight wearing a sexy black dress that was slashed down to her belly button and only partially covered her breasts.
Taylor, 31, plays a hunky firefighter in the brand new drama.
And Gaga, 26, did her best to rally support for the show's very first episode, which aired on US channel NBC on Wednesday night.
As she mingled with cast and crew members at the private party, she begged her 30million Twitter followers to tune in.
Gaga tweeted: "My bf Taylor is on TV TONIGHT!!! for the premiere of CHICAGO FIRE.Monsters, wanna watch it with me+chat online?"
She later added: "Time for bed. Thanks for watching. The cast works so hard and are great friends.x"
Her rally cry seemed to work - the premiere drew an audience of 6.4 million viewers.
But it lost out in the ratings battled to Hayden Panettiere's country-themed show Nashville - which attracted 9 million pairs of eyeballs to rival channel ABC.
Taylor and Gaga met on the set of her music video You And I last year.
They've kept their romance pretty private - but Gaga recently posted a photo of them smooching naked in a swimming pool.
And the model-actor spoke out for the first time last month to reveal he's smitten with the singer.
He told an American newspaper: "I don't think I've ever said anything publicly up till now. But I'm happy. I'm in a relationship and I'm happy. Everything is great."
|Gaga's man ... hunky star plays a firefighter in Chicago Fire|