I noticed Scribbles route (as unfinished as it is, since only the Therium and Alfy portions are complete) raises some global flags when you complete specific segments.
Like, even if you start from the beginning, if Therium's segment has been finished at any point in the past, Alfy's segment is unlocked. Same with Alfy's segment and the (currently inaccessible, but the option is there) Scribbles segment.
I don't know if it's because of the route being unfinished and that'll disappear as soon as chapter 1 of Scribbles is done, but I'm already imagining what would happen if that were allowed to progress in that direction... Maybe future chapters of Scribbles can raise flags that are checked in earlier chapters? Feels like a possibility.