Genji

Ebata Katsumi, 16 years old, 1st year student of Senior Highschool. Following his love Sakura, he went to the mysterious dimension of Japan and got involved in the fight between Genji and Heike. The actual historical epic took place in the Heian and Kamakura era, but the manga is somehow set in modern Japan where the characters can even go to Shinjuku. Katsumi looked very like Minamoto no Yoritomo who just passed away so the Minamoto family made him to be the fake Minamoto no Yorimoto so that the people from Heike family wouldn't know about it. The story depicts life and death in the Kamakura bakufu.

(from mangaupdates)