At the Infinite Fortress.
Like every day Douma and Akaza argued about simple things and it always ended in fights but that day Daki was toy in a fight because the two upper moons had accidentally destroyed her mirror when she was simply entered the room.
Many hours later a little demon with raven black hair and sky blue eyes entered the room. He was the same size as a 3 year old and also the mentality. His name was Giyuu Tomioka and had been turned back into a demon at the age of 8 by Kokushibo who had found him lost in the mountains.
Given his innocence and that he is adorable but also that he is fragile Muzan decided that Kokushibo will take care of it because the paternal instincts of the moon had resurfaced as for little Rui.
Kokushibo later decided to adopt the little demon like Rui.
Giyuu regards Kokushibo as his mother.
Returning to the present.
As Giyuu walked into the middle of the upper moons brawl, an attack from Douma unfortunately found itself in Giyuu's path. Daki who had seen the attack tried with his ribbons to stop it. Although she managed to deflect Douma's attack, part of it hit a surface on Giyuu's forehead, which fell to the ground.
When Douma and Akaza realized it was too late. Tears streamed down Giyuu's face as his lips trembled. He had a thin bloody cut that was beginning to heal.
Daki approached Giyuu and tried to make him not cry. Akaza started praying silently fearing the worst.
Despite Daki's attempt, Giyuu eventually burst into tears.
Giyuu: MOM, YESNN!
Silence ? ?
Then the three moons heard a huge crack indicating that the door leading to the room had just been broken. They looked behind them and paled.
Mom Kokushibo had just appeared!
Akaza to say despite being scared to death.
Akaza: We're screwed.
Kokushibo shouted in an angry voice: WHAT HAPPENED TO MY SON!
END