for iserlohn probably upright the fool or the world. he is both incredibly knowledgeable (when it comes to matters of pure fact and scientific deduction) and incredibly naive (when it comes to the culture of living beings) so he could really fit either. his journey on terra is a journey of recording the history of humanity on it as well as learning more about them as mortal beings in general. as a star (physics) he has a deep and instinctive knowledge of the fundamental rules of reality as well as being able to manipulate it (gravity for example) but these things are basically useless for predicting human behaviour so he can't really 'cheat' using his existing knowledge when it comes to navigating society, having to learn it just like anyone else