Rihanna @ a children's benefit at Vision Nightclub in Chicago

She could call it her good-works tour, but Rihanna is calling it "A Girl's Night Out."

"Girls always have more fun, so I thought it was a great cause for me," the Girls Gone Bad singer, 20 told PEOPLE after a performance Wednesday night at Chicago's Vision nightclub.

With her charity, The Believe Foundation, Rihanna and Island Def Jam, "got together with a local foundation in three cities and Escada and [the label's fragrance] Moon Sparkle" to sponsor the event, she said. "It was amazing." [People]

Source: bastardly.com