Alfie Allen is naked 16 minutes in episode 5 of season 1.
He proudly shows us his massive uncut dock. As his fellow actress says, he is a "serious boy with a serious cock".

Later in the episode, we get a partial butt shot of Gethin Anthony, after he gets a complete shave from his boyfriend Finn Jones.

Nikolaj Coster-Waldau is quite a twink. In this movie, he appears naked on his bed, and for a few minutes lies there, for us to admire. His cock is soft but pretty big and uncut. His body is muscular and his face is to die for! A lot of close up in this movie, so overall a good movie if you like Nikolaj.

In episode 5 of season 3, we get nudity from Will Tudor, Nikolaj Coster-Waldau and Kit Harington.
Will Tudor is naked in bed 51 minutes in the movie. As the steps out of the bed, we see his nice uncut penis. The picture is a bit dark. Then Will Tudor gets back in bed with his lover, and we see his bubble butt and somewhat hairy crack.
Nikolaj Coster-Waldau is naked 35 minutes in the movie, and steps in a hot tub. We get a good view at his butt and balls as he steps down in the tub.