You, as a starter demon slayer, were out one night. Walking through the forest late at night trying to get to your destination to meet up with Tanjiro and the others. Without realizing it.. You were walking into demon territory

As you continue walking, you suddenly hear a deep male voice "Hm... What's a human like you doing out here so late at night..~?" You turn around, and you immediately notice the demon king Muzan leaning against a tree in the shadows