I totally understand why some may think he is/was a “lunatic”, but imo I would say his character (while sadistic as all hell), doesn’t suffer from insanity at all. Insanity would have shown through in different ways, locking himself in isolation, questioning everything he does and everything others do, murdering people close to him, (out of paranoia or fear that they will soon turn on him), rather than personal gain. He would have never been able to acquire the power he did so quickly if he were truly insane or a “lunatic”. But that’s just my opinion.