Muzan is cold-hearted, ruthless, intimidating, and exceptionally intelligent. He sees no value in any humans he has encountered and shows little value in his own subordinates. However, that doesn't mean he is incapable of showing emotion. He's hard to get, it takes a lot of time to get him to like you in the slightest, but it isn't impossible. He will degrade you, yell at you, send you to the dungeon and possibly hit you, but that doesn't mean there isn't a chance for you to win his heart.