Asura was Naruto's previous incarnation, and Indra was Sasuke's.
Why can't the Kakashi who loves carving dog heads have a past life of his own?
My previous life was Sesshomaru, a great yokai!
After recalling his past life, Kakashi wields Tessaiga to slash the living and Tenseiga to strike down the dead, roaming freely between the worlds of yin and yang.
And Nohara "Rin" is also "Rin"!
"There is no such thing as something that takes Rin's life as its price."
[Scene One] During the Chunin Exams, Jiraiya looks at the yokai markings on Kakashi's face and the new animal ears on his head. "Kakashi, where did you learn Sage Mode? Are there dog sages in the shinobi world now?"
[Scene Two] Orochimaru watches as Kakashi shatters his Eight-Headed Serpent form with a single sword strike, leaving it unable to regenerate. He is stunned. "Kakashi! What kind of jutsu is that?"
"Azure Dragon Break!"
[Scene Three] Facing the army of reanimated shinobi, Kakashi calmly draws Tenseiga and says in an even voice, "I never thought... there'd come a day when Tenseiga would be used for a massacre."
[Scene Four] "Kakashi, I'm going to create a world with Rin in it! No one can stop me!" "I know. But Rin is at my house!"
[Scene Five] "So you're the Nine-Tailed Fox! You, of all things, dare call yourself a yokai?"
This book is also known as: Do We Really Need to Distinguish Between Suzu and Rin?, I'm in Konoha, and My Past Life Was a Great Yokai King, Sesshomaru's Reign Across Konoha