One month
Answer: One month, once a month. (Comes with the up probability of new shikigami)
Onmyoji is an onmyoji who originated in China. He knows how to observe stars, read people's faces, measure directions, know disasters, and find feng shui. A kind of monk who performs sacrifices. Due to modern historical reasons, onmyojis are no longer common in China. Most onmyojis in China are mainly engaged in observing Feng Shui and reading people's faces for a living.
During the Tang Dynasty, due to Japan's defeat at the Battle of Baijiangkou, Japan began to send Tang envoys to China on a large scale to study the culture of the Central Plains. Onmyoji and other concepts were introduced to Japan, and Onmyoji gradually became popular in Japan. ?