"I once believed that the road of happiness continued forever and ever into the distance. When it was destroyed, I realized for the first time that happiness lies atop a thin sheet of glass. And just as we were saved, there are those whose happiness hasn't yet been destroyed. So I wanted to get stronger and protect them."

(To Tanjiro) "How can you feel sorry for something that's killed humans? I've never heard of anything so absurd. But if that was how my sister truly felt, then I must carry it on. If there's a way not to kill these pitiful demons, I have to keep trying to come up with it. Without ever extinguishing the smile my sister said she loved..."