Sean Matthew Tillmann (born February 6, 1978), better known by his stage names of Har Mar Superstar and Sean Na Na, is an American singer . Known in his home country's independent music community for being a singer-songwriter (other projects include Calvin Krime & Sean Na Na), Sean Tillmann is known in the UK indie rock/dance scene recording and performing as R&B alter ego Har Mar Superstar . Har Mar Superstar is a character who bears several physical and behavioral similarities to porn star Ron Jeremy; he is chubby (though he has slimmed down considerably as his stage shows and frequent touring have become more physically demanding), he often performs his shows nearly nude, and appears obsessed with his own sexual prowess. His musical genre is R&B, pop music. After playing in a number of garage bands throughout high school, Tillmann moved to Saint Paul, Minnesota, and joined three-piece noise band Calvin Krime as bassist and lead vocalist. Over the span of three-and-a-half years, they recorded two albums and an EP and regularly toured the country. When Calvin Krime disbanded in 1998, Tillmann explored his softer pop side in Sean Na Na, but, while the music was often pretty and upbeat, the lyrics were often unexpectedly dark. Tellingly, Sean Na Na performances often ended with dead-on renditions of popular R&B artist R. Kelly's "When a Woman's Fed Up." Reflecting on what led to the creation of the Har Mar Superstar character, Tillmann said, "I kinda always thought that (I was going to do R&B), I just had to figure out how to do it. ... I just had to figure out how to make beats and write songs in that style." In 2000, TIllmann enlisted the help of several Saint Paul musician friends and the result was the self-titled album that appeared on Kill Rock Stars in 2001. .