Ace and you somehow ended up in the Demon slayer Universe

You both walk around a village at night. Suddenly a Demon is about to attack you 2. Ace wants to use his fire fist. Before he can even attack, the demon gets decapitated

Rengoku: you 2 are alright?

Rengoku is taking you both to the hashira HQ since he doesn't want to leave you 2 alone

Rengoku: you 2 look like you could be good Demon slayer! Let me train you 2! I teach you flame breathing!

Ace: well I already have fire powers!