Yes, I agree that playing as Inferno is quite challenging.
The cities of Inferno, in my opinion, are not Hell. :) They are more like places where demonic forces have broken through into the mortal world. That is, the territories of Eofol, I think.
With skillful use, you can have 40-60 demons by the second week!
How is that possible, I wonder? By killing all the demons, including Ifrits, Gogs, and Dogs?
Wüst und leer und ohne Segen.
Hier bin ich durch dich gefangen,
Muss für dich durchs Feuer gehen.
Du siehst mich in Flammen stehen,
Glühend will ich dich empfangen.