See in the first panel Saitama is like poke me in the eyes with the two fingers and he blocks it. Next he says he'll do it to Genos and he assumes the position however instead of using one hand he uses two thus the block doesn't work and hilarity and eye ball pain ensue.
**balasla used "*roll picture*"** **balasla rolled image**okay what shade of blue text is that? I do not know why but its aesthetically pleasing. . . .
Genos does, in fact, have eyes. While they are thought to be mechanical, due to how he "scans" things, the doctor he gets the modifications from makes sure he can remain mostly human despite being a cyborg. This results in his eyes clearly reflecting emotions, such as pain, or how they shrink in size when he's stunned from Saitama's punch
Along with that, he can feel them getting poked, as a safety precaution. I do not think he has to blink them, though.