The unspoken law of yaoi manga and sometimes slash fiction, which designates the taller character in the pairing as the seme/top. Occasionally subverted by authors, justified by "lower slays higher".
"What is this mangaka doing?! Is she really trying to tell us that scrawny piece of shit could top HIM? She's totally disregarded the Height Rule!"

"Man, I'm tired of reading all this fanfiction where Sam Winchester tops."
"What do you expect? Height rule."
by E. K June 10, 2008
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This is invoked mid-game in any competition when someone wants to cheat by changing the rules of the game.
Jeff K called Hacienda Heights Rules during the dodgeball game so that his team could add an additional player.
by SoPasDude July 1, 2023
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