If you already have one heart, that means the next one is the second event. To activate it, just fill the affection bar. Once it’s full, go talk to Dr. G in her lab in the afternoon, Lily doesn’t need to be there for the event to trigger.
I’m having the same issue. Lilly is nowhere to be found and all Dr. G says is that I should hang out with Lilly. It might be an issue with older saves since I had Dr. G with a full affection bar and one heart. The second event might not be triggering with the flag set by the previous event. Unless the second event is not on Monday afternoon.
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 😔!