Who? American TV stars.
Real? Yes, but it’s a comedy sketch with no actual visible sex.
Kevin Nealon and Jimmy Kimmel did a two-minute “celebrity sex tape” comedy sketch which appeared online in September 2009.
In the sketch, Nealon asks Kimmel for ideas on how to promote his new standup comedy DVD through “internet viral video”. Kimmel suggests making a sex video: “what I would do, I’d find the first celebrity I can, have sex with them”. Kimmel then offers to help, and things get raunchy.
This YouTube video is dated September 30, 2009, one day after (false) Jimmy Kimmel + Sarah Silverman sex tape rumors exploded online. Probably just a coincidence.