In the 4th anime, he was exactly just like the original panting. In the 5th anime, he has a body and doesn't stick out his tounge.
Legend
Aobōzu (青坊主Blue Priest?) are a type of Japanese yōkai (folk legend ghosts) that appear in 18th century artist Toriyama Sekien's book "Gazu Hyakki Yakō."
The aobōzu is depicted in the Gazu Hyakki Yakō as a one-eyed buddhist priest standing next to a thatched hut, however as there is no explanation of the image, the aobōzu's specific characteristics remain unknown.
It is believed that the aobōzu is the direct inspiration for the one-eyed priest hitotsume-kozōthat is present in many yōkai drawings, such as Sawaki Suushi's "Hyakkai-Zukan" published in 1737. There is also a theory that because the kanji ao (青) in its name also means inexperienced, it was depicted as a priest who has not studied enough.
Trivia
- He was called Aoi for the first few times he appeared.