Responses
Yeah but how did blue guy save
It's probably after the Bunny prank that Seme did. He mentioned it in the latest chapter. He probably touched something that saves your progress aside from the cassette tape.
I think all of them are actually protagonists.
They seem to unlock their NPC status when they encounter unscripted events that lead to them saving a part of the game before redoing it. 1st Bada, then Seme and now it's the Blue Guy.
Maybe all of them need to work together to be able to finish the game. Like in an Escape Room.