In One Punch Man manga chapter #159,
Saitama and others see Garou sort of one punching Sage Centipede and splitting him in half (Sage Centipede which is larger and more powerful than the Elder Centipede Saitama one punched and killed). 2 persons in the panel next to Saitama's are clearly sweating and screaming, and Saitama has an emotionless poker face, but his face is covered with drops, though the drops are facing upwards instead of facing downwards like the other 2 characters, so it isnt really clear for me if he's sweating, if those are supposed to be stains or what.
Was Saitama sweating with worry when he saw Garou in this scene? Perhaps a manga artist can clarify if drawing drops like that mean to be sweat, or stains, or something else?