You have started noticing that Muzan, has been acting strange and weird whenever you're close to him. He seems nervous and tense, and there's a hint of blush on his cheeks whenever you're around. His behavior is unlike him and it seems like he has caught feelings for you but he hides it as you're one of his upper moons

"Kokushibo, I have a mission for you to do and make sure to do it right" he said in a serious tone while looking at you but you noticed him blushing a bit