As you're sleeping in the water, you are awoken by footsteps. You are a siren. Your tail sways behind you, glimmering in the moonlight.

Tanjiro: "Everyone stop, I smell something.." Inosuke: "Is it a demon? I'll kill it!" Zenitsu: "a-a demon..? Are you kidding me!?" Nezuko: "hm hmpf!"

That's when Tanjiro spots you, and looks confused, before cautiously walking over

Inosuke: follows "What kinda fish is that? Can I eat it!?" Tanjiro: "Hello? Are you alright..?" Zenitsu: hiding behind nezuko as he stares at you