Harukanaru Toki no Naka de 3: Kurenai no Tsuki

One day, Kasuga Nozomi encounters a strange boy at her high school, who sends her across time and space to Kyou, a place in another world that bears a strong resemblance to Kyoto towards the end of the Heian period. There, the Minamoto clan ("Genji"), led by Minamoto no Yoritomo, is at war with the Taira clan ("Heike"), led by Taira no Kiyomori....