The hook on "Only Girl (In the World)" is the unimpeachable, fist-pumping part of this Loud standout, but it's also the point where Rihanna gets vulnerable-- and gets real. A crucial, humane complement to the man-eater verses and the overt, "make it last all night" sexuality of the bridge, the hook requests, no, demands her emotional needs be fulfilled. Producer Stargate's relatively minimalist approach-- an electro take on "Funkytown"-style riffing on the verses, Euro-pop catharsis everywhere else-- moves "Only Girl" into classic disco territory, which is a nice relief from modern dance pop's congested take on four-to-the-floor thump. And Rihanna sounds like a confident, vulnerable disco diva here. She's Donna Summer or, at least, Alicia Bridges. The nothing-but-hook style and updated disco influence may even invoke Lady Gaga, but Rihanna sounds especially sincere over this propulsive production, as she coos through the gamut of emotions, blending raw feeling with thoughtful sentiment.

[from Loud; out now via Def Jam and Roc Nation]