Yōkai

Even kappa can be washed away by the river.
~Japanese proverb

Legendary Japanese supernatural creatures today. Spooky, cute, funny -- they really cover all the bases.

A kappa (an amphibious yōkai demon said to like cucumbers...an old tradition was to write family members' names on cucumbers and send them afloat on streams to mollify the kappa)
by Katsushika Hokusai

Nurikabe (a plaster wall said to manifest as an invisible wall that impedes or misdirects travelers walking at night)
from Bakemono no e

Rokurokubi (There are two types of Rokurokubi: one whose neck stretches, and one whose head comes off and flies around freely)
from Bakemono no e

Hahakigami (broom spirit)
Toriyama Sekien

Mujina (shape-shifting badger demons who deceive humans)
from the Wakan Sansai Zue
Terajima Ryōan

Onibi (ghost light, spirits born from the corpses of humans and animals, often blue)
Wakan Sansai Zue
Terajima Ryōan

Bakemono Chakutōchō (a tōfu-kozō, a yōkai that takes on the appearance of a child possessing a tray with tōfu on it. Sometimes teased by other yōkai for being weak yōkai)
by Masayoshi Kitao