What if the king of demons...
is like king in one punch man? Ik demons can sense strenght but maybe they all thought demon king was so strong that they couldnt mesure his strenght
That would make sense because Titan king's children are absolute fodders, if demon king is strong then titans are basically demons but weaker mainly because of the 47 king.
I imagine some funny scene like robot not detecting king's strenght because he is too weak and running away like that scene with king and the powerscaling mask