Keitaro Gentoga is a young man with a spiritual constitution, the tutor of Yayoi Hozuki and the childhood friend of Eiko Hozuki. He can feel the presence of supernatural beings, and his presence attracts supernatural beings, even Yayoi who can see supernatural beings is often ignored. In order to not be easily possessed, Keitarou was taught by his grandmother to exercise and meditate regularly, because supernatural beings have difficulty possessing people with healthy bodies and minds, as a result, Keitarou is quite athletic, able to run around the altar, then carry Yayoi while escape from the pursuit of malicious gods and spirits.