Fashion designer Erin Fetherston and Cobra Starship lead singer Gabe Saporta are officially a couple. The two were making out like teenagers while Duran Duran performed at Paper magazine’s “Beautiful People” party at Good Units Wednesday night. Saporta introduced platinum-blond Fetherston as his girlfriend to friends and said they’d been seeing each other for about four months. Fetherston was engaged to French artist Hedi Ferjani in 2009, but they never married.