Okay, I was a bit curious about this “Special stage” that Miku hint at, so I google “Kyoto stage” and the immediate result was Kiyomizu-dera, a Buddhist temple.
The stage that Miku was referring to, is probably the open wooden stage that is part of the main hall, which is situated 13-meter above the ground. And apparently there "was" a tradition from the Edo-period that if someone were to jump and survive the fall from the stage, he or she will have their wish be granted. That definitely worries me, now my hype has been replace by anxiety, and I hope nothing serious like that happens, accidental or not.