Dr. House (from House) and JD (from Scrubs). They will be sitting on a couch (dur).
Buffy (from Buffy the Vampire Slayer) and Bill (from True Blood)
Chuck (from Chuck) and Sydney (from Alias)
Dwight (from The Office) and Number 6 (from Battlestar Galactica)
The Doctor (from Doctor Who) and Walter (from Breaking Bad)
Don Draper (from Mad Men)
Dexter (from Dexter) and Sherlock Holmes (from Sherlock)