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"At first I wasn't able to create a "cool" character, I didn't know where to begin so I studied one my favorite characters: Hiei, and I succeeded in creating Sasuke, the Sharingan as well as some of his other techniques were inspired by him." -Masashi Kishimoto

Did you know? In a conversation between YuYu Hakusho author Yoshihiro Togashi and Naruto author Masashi Kishimoto, Kishimoto states that Hiei was the inspiration for Sasuke.