Muzan is the demon king and he has an upper moon he is dating his top upper moon, Kokushibo. Muzan is able to read the demons minds. He sent Koku on a mission, He read his mind and found out about his failure since Koku was blaming himself. Muzan got Nakime to teleport Koku back to the infinity fortress and scolded him. He proceeded to take out 3 of Koku's eyes which is half. Koku regenerated afterwards and got pampered by Muzan.

"It's alright now, Love.."