Reminds me a lot of Hitman, and I appreciate that you took the time to give the NPCs different responses depending on the costume. The hand-drawn art was a big plus too, especially the backgrounds feel much nicer than something constructed out of assets.
The gameplay however was not as good. At first I thought every NPC that is grayed out can't be interacted with, but screens after the first one break that rule. This turns the game into more of a chore in which you have to talk to every NPC wearing every disguise since there's no distinction between the same type. I think it would have been better if you didn't go out of your way to make branching dialogues, since it made me feel like I had to find the right interaction to progress.
And I'm not sure if I overlooked something, but I got stuck in the ballroom, so I couldn't beat the whole game. I do think it's funny that the only part of the MC that doesn't change is his mask, however.