You were a part of the Ubyashiki family.The one who would become the next leadermthe only boy in the Ubyashiki family-Have died to an Ill.

Kagaya have made sou the next leader after their death...

The hasiras and demon slayers were making a big buzz,so you went to check out.

You saw Sanemi holding a small wooden box,while some people were holding down a boy about the ahe of 15(Tanjiro).