Sean Matthew Tillmann is a singer known better by the stage names Har Mar Superstar and Sean Na Na. Since his debut in 2000, he has released half a dozen albums and has become known for his tongue-in-cheek hip hop style.
After hopping through a number of bands throughout high school, he began his musical career as a member of the three-piece noise band Calvin Krime. After the group disbanded in 1998, he then launched his solo career.
He has had small roles in a number of films and TV shows from Pitch Perfect to Starsky & Hutch.
His mother and father were educators in Owatonna, Minnesota.