Manually replacing fanart for a non-album artist — where do I go?

Say I’ve got one song by The Cure from a soundtrack, and I don’t like the clear logo fanart that was scraped (too dark!). Normally, I could rectify this by dropping my logo.png of choice inside the artist folder. However, The Cure has no artist folder in my library, it only exists as a track in “The Crow” under Various Artists.

I can’t just make phantom artist folders for fanart purposes, can I? I’d actually prefer this method if it were possible, since I have an outside program clustering my fanart by artist… but I’m assuming Kodi will look right past a directory with no actual music inside. Is my only option to just manually replace art within Kodi under the artist options? Or is there some obscure cache sub-folder I could navigate to outside of the program to do such things?

My eventual goal is to contain as much fanart files within the native library folders as possible. I figure this would “future-proof” my library and allow it to play nice with any fanart-oriented media player I may throw at it. Cool