Onmyo Kaiten Re:verse

The anime is set in an alternate version of Heian-kyou, the old name of Kyoto and the capital during Japan's Heian era. This alternate version of the city is named Denji Heian-kyou. A delinquent high schooler named Takeru Narehira resides in our world, but after an unfortunate accident, is transported to Denji Heian-kyou.

Here, he immediately meets Tsukimiya, a woman he has seen many times before in his dreams before. Hardly a moment passes after that encounter when Takeru and Tsukimiya encounter an oni monster, and lose their lives.

Takeru awakens, stunned to find himself again at Denji Heian-kyou. He puts together that he has the power to go back in time. Now he resolves to learn this world's version ...