willing suspension of disbelief

You accept that the reality presented in the show can be taken at its own value despite any mismatches with objective reality, because questioning the fictional reality makes fiction stories lame.

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Wait...
Is this a Game of Thrones question? Keep it in its own thread, sheesh.

Plenty of us don't need hyper-sexualized dramas for entertainment.
The the internet has that covered, and and you can get it without all that annoying drama.

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The basic rule of fantasy writing is to make the characters paragons of epic legend. So by appealing to our own sense of god-hood, they make us sympathize with those who represent a tangible struggle which we only face in our sensibilities.