From the first episode of Death Note:
名前のあとに人間界単位で40秒以内に死因を書くと そのとおりになる
Questions:
What purpose is "人間界単位で" ("within human-world units") serving in this sentence?
Grammatically, "人間界" is a noun and "位" is a counter. But the thing that's being counted here isn't literally human-worlds, is it?