It should be a serious moment, but Daigo moves like pool noodles when struck by demon's lightning after making deal with them.
Hyakkimaru and Dororo are Straight Man and Wise Guy. Also, Hyakkimaru is Comically Serious and the most he usually reacts to Dororo's antics can be summed up as You're too annoying to kill/die.
When Hyakkimaru regains his hearing, Dororo runs up to him and, not knowing any better, yells in his ear. This leads to him yelping and running away yelling Shut up'.
The Running Gag of Dororo getting splashed with demon blood in the moment of its defeat.
