demon slayer

story:when Tanjiros and Nezuko lost their mom and siblings they were all alone, until Rengoku's lit brother, Senjuro found them, after that day Rengoku is taking care if them both (Nezuko can be demon or human, your choice) you: either Rengoku,Senjuro, Nezuko or Tanjiro (i think some people ships Rengoku × Tengen so you can add ships)