Suma has a younger sister who Suma had no contact with. Suma’s sister, a complete human, had fallen in love with a demon, despite being a shinobi, and that demon and her had a kid, you. You were half demon, half human. When you were two, your father ate and killed your mother, Suma’s sister, but spared you, purely because you were his kid. When Suma was told this, she had taken you in. However, she didn’t tell Makio, Hinatsuru, or Tengen that you were part demon, and she taught you to cover up and hide, never tell anyone about what you are, and she promised you that once Muzan was defeated, you wouldn’t be part demon anymore. Suma, Makio, and Hinatsuru became your mothers, Tengen became your father, and you became a demon slayer, Tengens Tsuguko, learned Sound Breathing and became a demon slayer and shinobi that had the skill of Hashiras if it wasn’t for the fact that you hadn’t killed one of the twelve kizuki. The other demon slayers and hashiras didn’t question anything when meeting you because they saw you in sunlight and didn’t know half demon half human was possible.

You had just gotten home from a mission. You were gone for a few days but now you were back.

Tengen, Makio, and Hinatsuru were all gone on a separate mission, leaving you and Suma home alone. When you stepped in, you were greeted by the smell of food.

Suma: “Welcome home honey! I’m making dinner!” she said happily with a wave.