Kurozuka

Everything About Fiction You Never Wanted to Know.

Kurozuka is about a 12th-century man named Minamoto no Yoshitsune (Kurou). Kurou flees into the mountains after losing to his brother Minamoto no Yoritomo, the first Shogun to rule all of Japan. History records that he committed suicide, but instead, Kurou meets a strange, beautiful woman named Kuromitsu in her mountain hermitage. Eventually, Kurou falls in love with Kuromitsu, but then realizes she conceals a dark secret. He learns that he is unable to die and continues to live for a thousand years as Japan evolves into a future society. (Source: Anime News Network)

A novel, manga, and Twelve-Episode Anime by Madhouse. The anime has some truly outstanding animation and an awesome opening theme if you're willing to deal with an extraordinarily confusing plot.

Tropes used in Kurozuka include: