The Edo period was an era when demons were rampant and onmyojis were glorious. There would always be onmyoji families settled in almost every capital city. Especially in Kyoto, a school specializing in training outstanding onmyoji - Sun and Moon Academy was opened.
Sawada clan Kotsuna, who has a unique talent, only summoned an extremely weak shikigami during the summoning ceremony that attracted everyone's attention. He had no choice but to sign a contract with it.
However, it was this weak shikigami that added a different color to Sawada Yanzuna's ordinary life...