frustrated (as if having a fight with someone)
not to be confused with "air punch" or "punch the air" which have total opposite meanings (very pleased)
Person 1: *watches a video absolutely destroying Person 2's arguments* Dude, Person 2 be punching air right now.
Boys who enjoy yaoi (a genre in Japan that contains sexual and/or romantic relations between two men); literally translates to "rotten boy"; corresponding female : fujoshi