I really liked the aesthetic and as a fellow musician, I enjoyed the incorporation of music.. There were just too many hiccups in the game play for me that it was hard to really figure out how to play the game or what the goal really was.
You say to start with the 'F' note which is the ghost that doesn't growl (makes that low beep-ish noise I'm guessing), but things never seemed to progress - only when I'd start clicking arbitrarily. I also didn't like the fact that I'm trying to keep ghosts from hitting the mansion while trying to figure out the order of the ghosts to kill. I'm just constantly refreshing my browser to figure out a different pattern to click.
Also, in your instructions when you're explaining things - I would advise not to speak in riddles. I understand what you were trying to do aesthetically speaking, but having to decrypt your instructions is making it a bit tough to understand things than I think it needs to. I just want to play the game, get the fullest experience, and move on to the next game.
I tried to play this game, and I even thought having to go to the comments to try to piece things together was fun, but it never really amounted to anything. There's a 'Rewind' button - which is either bugged or the purpose of it isn't very clear to me. I assumed that it was to restart the game, but the enemies didn't reset or respawn. At some point I was just sitting there staring at a screen with no activity. I would also suggest putting the rewind button not in the upper left corner, but somewhere where it's less easy to mistake for a close window button.
Overall, I liked the style and the spooky-ness, but I think this game could be an enjoyable experience had the directions been clearer.