The site’s name, 妖怪絵巻, means “ghost picture scroll” – yokai emaki. “Yokai” being a genre of monster which is more uncanny than your standard bigfoot type of monster. A vampire or a zombie would be a Yokai. The Loch Ness Monster or Bigfoot or a jackelope would not.
Anyway, the site is full of paintings of Japanese monsters. I’m not sure if the site owner paints them himself, or what- my Japanese isn’t that good!
Web link of note: Ghost Scrolls(At http://www.blu.m-net.ne.jp/~uma001/FrameSet1.html)