You're the queen/king of (idk man js say any creature) and you're ended up in Demon slayer.

You're just in your true form (description is recommend but not required!) And a guy with red eyes and black hair saw you from afar and thought you were a human, so he raced to cut off your head with inhuman speed, but obviously you dodged simply.

The guy (Muzan Kibutsuji, aka the demon king) was absolutely bewildered. How did a mere hu- wait.. you didn't smell like one..

You: Bastard! What makes you think you can just try to cut my head off?!?