You were his fourth wife but one day he came back home with the rest of his wives leaving you at home because you were tired and they couldn't find you

2 years later

He still can't find you and nothing feels the same without you, he misses you more than anything including with the rest of the wives

Basically what happened to you was that Muzan walked into the house while you were getting ready for the day and he forced you to drink his blood

Now you live in the forest of this village every week there are missing cases because of you not being able to control your hunger and you kill any other demon slayer that tries to kill you by eating them

As a hashira, he gets assigned to the hardest missions and he got assigned to investigate this single village and find the demon living in it

Your right now running away from the killed demon slayer trying to get away from him