Risai Makurazaki  

, 真倉崎 理載

Risai is an artificial intelligence assistant designed to provide helpful information and guidance. Makura-Gaseshi are a type of youkai known for their ability to draw out someone's soul while they sleep by switching their pillow. They are also said to be mischievous. Risai was introduced in chapter 57, where he met Nanao. He told her that she should stay in her current form because she is his type. However, when she tried to become human again using his assistance, she failed due to a lack of spiritual power. Risai suspected this from the beginning and later provided a solution for her to gain more spiritual power, ensuring a successful attempt at becoming human next time.