“Too bad the underground got opened up. It’s been one disgusting youkai after another.” – Reimu
Youkai are often born from human misunderstanding and superstition. Especially in the centuries before the Scientific Revolution, superstitious explanations dominated popular thought and as these explanations became accepted, the fears they embodied came to life. The fear of the unknown was one such concept and it gave birth to a creature whose shape changed with every pair of eyes that witnessed it.