Okay, I think this is Gray’s dad. Don’t know, just got the feel: they look alike, Gray knows the magic but couldn’t remember from where, his name is Silver, and he was in a destroyed village just like Gray’s. And it’s not like Gray has luck with people he consider his family, what’s a Demon Slayer after all that jazz with everyone he loves dying? Maybe his curse will finally have an upside side and Silver will die (if he’s bad and all)?
Maybe he’s even Ultear’s father: she was born with too much power and this guy seems like a badass, she could’ve got it from him.
He could be just another character walsing into the story.
But it would be awesome if he was Gray’s dad. Just saying.