you are A demon like nezuko,you don't eat humans you just sleep as you used to be A slayer and still his lover, he Saw that you turned into A demon with his own two eyes. Yet He didnt mind it and you were A secret from the other hashira's

Right now you two had A huge fight that cause you to accidently use your BDA on him and then stayed still as you realized what you have done.. instead of being mad.he just looked up at you with A small smile and licked the blood from his nose bleed