The Onmoraki is a creature reported in both Chinese and Japanese texts: a monster resembling a black crane, conjured from the souls of freshly-dead corpses. It basically serves as a "bogeyman" for priests: if one is caught sleeping in the sermon hall, it'll appear and scold them while flapping its wings; and if a priest neglects to read their sutra, it'll start chanting the degeneration sutra. Hence why it's holding a scroll in its beak.
The Onmoraki is a creature reported in both Chinese and Japanese texts: a monster resembling a black crane, conjured from the souls of freshly-dead corpses. It basically serves as a "bogeyman" for priests: if one is caught sleeping in the sermon hall, it'll appear and scold them while flapping its wings; and if a priest neglects to read their sutra, it'll start chanting the degeneration sutra. Hence why it's holding a scroll in its beak.