I genuinely loved this. Fun concept, brilliantly executed and made me smile constantly. Art, music, sfx, story all matched perfectly with the theme as well.
I wonder if you made the punching mechanic too satisfying! It felt super responsive and juicy, I flippin loved whacking my opponents, so it genuinely felt hard to resist haha.
On a more serious note, if you continued development I'd love it if the believability went up for things other than just hitting them. Eg if you swing and miss only inches from them - it would add an extra layer of skill, and keep the player active (I found on the third guy a lot of the time was waiting for them to throw their punch).