Game of Thrones is an American fantasy drama television series created for HBO by David Benioff and D. B. Weiss as showrunners and main writers. It is an adaptation of A Song of Ice and Fire, George R. R. Martin’s series of fantasy novels, the first of which is titled A Game of Thrones. Sheldon, Leonard, Howard, and Raj are all fans of the show.
In “The Russian Rocket Reaction”, Leonard and Sheldon drool over a sword from “Game of Thrones”. They decide to start a fantasy sword collection together and haggle Stuart down to $210 from $250.
In “The Comic Book Store Regeneration”, when Raj and Leonard are debating whether to meet who they think is Nathan Filion, Raj mentions that they met the actor who played Jon Snow (Kit Harington), and he was a jerk, but they still watch “Game of Thrones”. Leonard points out that the reason Harington was a jerk was because Raj rear-ended him.
In “The Skywalker Incursion,” when Amy compared Bernadette and Howard picking champions to a trial by combat, Penny compared it to the duel between the Mountain and Red Viper. When Bernadette asked if Leonard made her watch it too, Penny answered that she actually liked it because it has dragons and coitus.
In “The Application Deterioration”, Raj mentions the events of the episode “Mhysa”, in which Balon Greyjoy receives a box from Ramsay Snow containing the severed penis of his son, Theon Greyjoy
And there was a whole Season 9 episode, “The Viewing Party Combustion,” based around the gang watching an episode of the HBO show. Stuart (Kevin Sussman) even showed up in a Jon Snow costume, which set up Raj (Kunal Nayyar) to make the show’s best-ever Game of Thronesjoke when comparing their night to the show: “Stuart’s dressed like a member of the Night’s Watch, and they don’t have sex.”
The presence of Jon Snow’s sword Longclaw in the background means there’s kind of a Game of Thrones reference in every episode. All men must die, bazinga.