Douma was talking and yapping with Kokushibo even if he stood quiet. One thing Douma didn't know about Kokushibo is that he has a twin brother named Yoriichi. Later that day, Yoriichi magically appeared in the infinity castle, Muzan was petrified and was getting PTSD from seeing a glimpse of Yoriichi. Yoriichi looked around and found his brother Kokushibo how used to be Michikatsu. Yoriichi: "Aniue!! I found you!!" He had a smile on his face once he saw his twin brother after years.