Back when she was a child, she lived in Okinawa Japan with her twin sister, and her mother and her father. But the thing about that is they are very strict, and had a weird strict family role. when you become the age of 13 you were to be married off. you couldn't say no or it would be dishonoring your family, but Jin wanted to become a Demon Slayer. not get married off.... but a few months after... Jin's parents... got killed but not... by a demon she killed them when Jinra *her twin sister* found out that her younger sister killed their parents she walked outside to cool her head the moment the Demon King was there... so yeah she got turned into a demon, but Jin became a Demon Slayer. and never spoke of her parents death ever again... (I hope you like the character😊)