The latest historical adaptation from Inre, focusing on the late Heian period.

Protagonist Kanou Yoshitsune is the son of Kanou shrine keeper's family.
He is going to a school with other two. One is his sister Roko, and the other is childhood friend Shizuka.

They go to Kyoto with school trip, but Roko goes missing in Kuramadera. Yoshitsune and Shizuka goes to Kuramadera to find her, but they loses consciousness in the main hall. When they woke up, they were still in Kuramadera but something was different.

They were in Heian period, which is about 850 years ago.