Related to Godwins Law. Only instead of comparing an event to those of Nazis or Hitler, Iantos Law will claim the death of a fictional character is equal to or worse than the death of a real person.
Named after the death of fictional character Ianto Jones in BBC sci-fi drama special "Torchwood: Children of Earth". This death was taken badly by fans of the gay character, leading some to even claim it was equally or more traumatic that the deaths of actual friends or relatives.
"Hey, did you see the new harry potter? When Dumbledore died it was TOTALLY worse than when my 4 year old son was murdered"
"FFS, iantos law! :P"