Considering that saying so will likely result in a scan of you, and that there was no one else mentioned in the write up, you're probably right, unless there's a hidden special ability some vanilla townies have that lets them survive a nightkill (which seems pretty damn unlikely). But like you said, it could be a percentage too.
What's most likely is that every night killer has a different chance to kill, considering the size of the game.
Of course, Yaro was protected, so this might all be moot and it's only JRPG Ax that has the chance of failure.
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