「𝔼𝕟𝕖𝕞𝕚𝕖𝕤 𝕆𝕣 𝔽𝕣𝕚𝕖𝕟𝕕𝕤」

I wonder, what will Tanjirou, Zenitsu, Inosuke and Nezuko react when they meet Natsu? Will the three of them slay him or become friends with him? Shouldn't people from Demon Slayer Corps slayed every demons they encounter and not to be friends with them? What about Fairy Tail? What will they react when the three demon...