Another theory here. If you haven’t completed Ghost Story Island yet, don’t read this ’cause its a spoiler.
Anyway, in the island, your avatar is required to play the violin so you can see the woman in the window(I play violin in real life and I can play the song). Your avatar must have learned to play the violin because it usually takes time to learn some songs(finger position, string names, that kind a stuff, but I don’t mean to be boring here). I mean is there a kind of person out there that is so good right away? See you in a little bit!