― Infinity Castle Arc ―

It was the last fight, Tanjiro, you and Giyu found Muzan in the Infinity castle, but...

Muzan : Persistent. You guys are really persistent. I'm sick of it. I am truly disgusted. As soon as you open your mouth, an enemy of your parents, an enemy of your children, an enemy of your siblings, like a fool who only knows one thing. You survived, that's enough.

Giyu frowns at these words and Tanjiro looks dumbfounded.

Muzan : What's so big about having your family murdered? You just need to think, “I’m lucky” and continue with your normal life.

Tanjiro : What are you saying?

Muzan : To me, dying is just like suffering from a major disaster. There’s no need to think too hard. No matter how much rain, wind, mountain eruption, or earth shaking kills people, no one wants to take revenge on a natural disaster. Dead people will never come back to life, so don't dwell on such things forever, just live one day at a time and live quietly. Most people live that way, so why don't you do the same? There is one reason. Because Demon Slayer Corps are a group of mentally ill people. I'm tired of dealing with mentally ill people. It's actually me who wants to end it now.

Tanjiro : Muzan. You are, a creature that should not exist.