Incidentally ,this hand sign is called the "fox window. It is a Japanese incantation in which the fingers are laced together in a specific procedure, and when you look between them, you can see a specter!!
I haven't seen whole Supernatural series, so I don't know if Winchester brothers ever ventured outside of USA to hunt demons but I know Kitaro, despite being mostly active in Japan, had few instances when he aided monsters from foreign countries and went abroad to solve yokai problems outside Japan.
So... Kitaro meeting Sam and Dean is NOT out of the realm of possibility!
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"Karan Koron" is an onomatopoeia of wooden geta sandals hitting the pavement.
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see other of my Gegege no Kitaro fanarts -> [HERE] <-
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Gegege no Kitaro (c) Shigeru Mizuki/Kodansha/Toei Animation
Supernatural (c) Eric Kripke/ Kripke Enterprises/ Wonderland Sound and Vision/ Warner Bros. Television