Tengen uzui is 15 and is a female she was raised as a shinobi. Uzui ended up running away and leaving the shinobis. Uzui real family is the kamados and when tanjiro found uzui past out brought her back to his house. When they realized they were siblings the shinobis had taken uzui when she was two years old. Tanjiro and nezuko are happy to be reunited to uzui but every happy ending always has something bad happens at some point. Tanjiro was selling charcoal in the town and nezuko was staying at a friends house. When tanjiro and nezuko was heading back to their home they saw a scene they never wanted to see in their live their family was attacked by something. They thought the worse. My au I don't own the characters I only own my oc.