Since his mother's death when he was very young, he was taken care of by his older sister, Yukishiro Tomoe. Ever since, she has taken the role of both mother and sister to Enishi. Later on, he realizes that his sister was married to the Battousai. After the "kidnapping" incident of Tomoe, Enishi returns to see the Battousai slash through his sister [discussed in Tomoe's profile ^^;;]. Filled with rage, Enishi disappears for some time...building up to avenge his sister.

Enishi finds himself in Shanghai, where he was adopted by an extremely rich family. He kills them later because he couldn't stand their happiness. Taking their money, Enishi becomes a mafia boss. He also sold the "invincible" ship to Shishio (later gets destroyed anyway, LIAR!!!).

He uses the weapon, Watou. His fighting techniques include the Garyu Watoujutsu and the Kyoukeimyaku.