Pink Tentacle has a fantastic post about monster paintings called youkai in feudal Japan (Edo period) by a relatively unknown artist called Sawaki Suushi.
This one to the left is Nurarihyon, the house guest from hell:
In the Edo period, Nurarihyon came to be known as a mysterious old man with the uncanny ability to sneak into homes and “take over.” When the residents of a home encounter him sitting around drinking tea, they are unable throw him out and cannot help but treat him as the head of the household. Nurarihyon is said to be a highly respected figure in the world of youkai.
Link - via Quiddity