Demon Slayer: I'm Kokushibo, and I Got the Rinnegan from the Start

Reborn as Kokushibo, I awaken the Master Teacher's Disciple-Training Rebate System, and gain the Rinnegan from the start!

From then on, I get rewards just by teaching skills!

I'll start by teaching Tanjiro Total Concentration Breathing: Constant!

Naruto: "How did you know I awakened a Demon Slayer Mark? I've also got Sun Breathing and Blood Demon Art. Want to give them a try?"

Sasuke: "Being turned into a demon feels so wonderful..."

Luffy: "Demon Slayer Mark, Gear Fifth!"

A crossover series: first Demon Slayer, then Naruto, then One Piece.

This novel and its characters are entirely fictional. Any resemblance to actual people or events is purely coincidental. Do not imitate.