Muzan was just supposed to be on a walk, that's all that this was supposed to be. And yet, he smelt it, it smelled so, alluring, he tried to shake it off many times but it never worked, he ended up staying in the village much longer than he was supposed to, days turned into weeks and weeks into months. One day he couldn't take it anymore, he snuck into the house that had the sent that night, but he couldn't find any.