Fun illustrated overview of Japanese preternatural creatures.
Just the title is a bit overselling. Most of the yōkai aren’t really aggressive. They won’t attack you unprovoked – or at all.
The Azuki Arai (小豆洗い) may sing about catching humans to eat, but they never harm anyone.
On the other hand, if you want to be on the safe side, you may want to bring along a bottomless ladle, so the Funa-yurei (舟幽霊) can’t bail your boat full of water when you meet them.