First, she doesn't do that. There have been generation of Hakurei Miko protecting the balance of Gensokyo (and i doubt Yukari is dumb enough to let a squishy (albert nigh-unkillable), short-life human to be a keystone). Secondly, even if she is, that's in the Cosmic Keystone's area, not this. Magic don't disappear if she die.

Community content is available under CC-BY-SA unless otherwise noted.