Har Mar Superstar is the sleazy alter-ego of Sean Tillmann, who often performs in nothing but undies and a thin mustache. Despite this jarring performance style—which resulted in a 2002 public lewdness allegation—Tillman's greasy R&B is surprisingly smooth, rich, and velvety, not unlike creamy Jif peanut butter. Following 2013's Bye Bye 17, this month he unleashed a brand-new record, Best Summer Ever, which was produced by friend and Strokes frontman Julian Casablancas. Its 10 tracks set Tillmann's sexy croon to synthy electro-pop beats, punk-infused fuzz ballads, and a one-minute acoustic serenade to his radiator. CIARA DOLAN