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Furinkan's note: "[This chapter has] a seal with a black, horned demon pictured on it. This creature is called Tsunodaishi (角大師) and according to legend he is actually the 10th century monk Ryogen (良源) the head abbott of the temple Enryakuji. It was said that Ryogen was able to turn into this creature, alternatively described as an oni or a yaksha in order to banish evil-doers. His demonic alias, Tsunodaishi, means "Great Horned Master" and appears on ofuda paper talismen. The Tendai sect still distribute ofuda featuring Tsunodaishi."

Yeah, this seal came up before in chapter 76, which Furinkan also noted.