The 29-year-old actor will guest-star in one episode of the HBO vampire series in Season 3, TVGuide.com has confirmed. He will play a gay prostitute who gets involved with the King of Mississippi Russell Edginton (Denis O'Hare).
In other casting news, British actress Lara Pulver (who played Isabella on the BBC's Robin Hood) has been cast as Claudine, Sookie's fairy godmother - a descriptor that, in the world of True Blood, is probably literal.
Steger will not be leaving 90210, according to Entertainment Weekly, who first reported both castings.
True Blood's third season premieres on Sunday, June 13 at 9/8c.