You guys are right, there was a bug in the NPC affection logic. I already fixed it, but the problem is that I didn’t make a backup of version 0.1.12 to release a quick hotfix. So yeah, it’s fixed, but it won’t be available until version 0.1.13, which drops in two weeks.
The only workaround would be starting a new save file and going straight for Dr. G’s route to see all the new content, since you’d begin with 0 affection and wouldn’t run into this bug.
This really sucks since it basically blocks access to most of the update: two Dr. G events, the dungeon, the boss, the enemies, etc. basically, because of this bug, the only thing you can access right now is the Halloween event 😔!