DemiSlytherin
The Tsugikuni name may have died out, but the line still have descendants no matter how washed out the blood is.
When the pillars under the 96th Oyakata-sama of the Demon Slayer Corps were sent out to the Eclipse Estate following an attack, they did not expect to find the only remaining descendants of the youngest Tsugikuni to end up with fates comparable to how the three siblings from the Sengoku era had.
The only remaining survivor was taken back to headquarters for protection, the family's youngest and only daughter - Tsugihana Kagami - who then rose the ranks years later and took after the family's long held position as the Eclipse Pillar. Years later and she meets her distant relatives, the Tokito twins. Will she be able to keep her only remaining family close? Or will she lose her family like her grandmother did centuries ago?
"If my purpose in life is to be the Mirror who can reflect the truth and bring clarity to our bloodline no matter how bloodied the reflections are, if it will help bring an end to Kibutsuji's reign, then so be it."