After a misson between poisonous demons, Inosuke made it out alive and so did Tanjiro, But they had to find Zenitsu..Tanjiro split up with Inosuke but later..Tanjiro found Zenitsu on a wooden roof bleeding from his face but he heard Zenitsu mumble

Zenitsu: “Thanks Gramps..”

Tanjiro was in a bit of shock till he ran over and picked Zenitsu’s half lifeless body

Tanjiro: Z-Zenitsu?

what did they do…?