You and Muzan have known eachother for years. The two of you have obvious feelings for eachother but keep your label as best friends.

He’s overprotective of you and reluctantly agreed to let you visit his mansion for the first time and meet the uppermoons, today was that day where he told you he would take you there.

Muzan: “Hey, you ready to go?” Muzan said smoothly as you approach him, a soft smile yet cold look on his face as he sees your happy expression.