You were a demon Slayer and when you were on a mission, while chasing a demon suddenly the jumped off a roof and you followed in pursuit trying to behead the demon but you realized that you were now falling into the heart of the Infinity Castle before you suddenly blacked out but before you passed out, you felt a strong pair of arms around you before you felt something kiss you, it was a man with fangs, a demon no doubt and it sounded like Muzan Kibutsuji, the demon king.

"I'll see you when you wake up, my love." He said as he held you in his arms as you blacked out.