chill bro 1: yo, did you hear what chad did last night?
chill bro 2: yeah, he totally pirroned that sorority chick!
chill bro 1: dude it was so fucking loud wtf.
chill bro 2: people are nuts man. at least he got some.
Pirobo is somebody you find despicable and irritating I would say the best word for it in English would be "Prick" like in the sentence, you are such a prick.
"Ese pirobo se me coló en lafila "
"Por qué esos pirobos no contestan "