Fun fact: This is actually one of the very few times the translation squad for this game truly and epically messed up (because 99% of the time, they did a really great job). These people weren’t talking about Prompto, they were talking about Cindy.
A more accurate translation would be something like:
Dude 1: Did you see the blonde with the bangin’ bod walking around town?
Dude 2: And she had a really cute face, too
Dude 1: Chicks like that are awesome. But I’ll bet she’s high maintenance.
How can I tell, despite the only defining characteristic being “blond(e)”?
The term stairu ii used in the first line is slang referring to someone with very nice body proportions: Tall, or tall-looking due to long limbs; slender; and mature-looking (ergo, a certain amount of curves). I’m not gonna say it’s never used about guys, but... usually not? Either way, it’s not really a term you’d use about Prompto, he’s too... cute.
Similarly, they use ko, which usually refers to either a child or a young woman. Also, the last line, yappa burando-hin suki toka, otakai kanji kana?
Burando-hin, or brand items, refers specifically to high-end brand name fashion (Hermes, Burberry, etc), and the guy is saying that there has to be a downside to a girl that cute, so he’s convinced she would expect expensive brand presents from whoever she was dating. Not only is the market for burando-hin smaller for guys, it’s stereotypically (in Japan, at least), seen as something women are into.
So either there were words the translators didn’t know, or they were like “blonde??!” “...Prompto, I guess?!??!” “....wtf, that makes no sense, but okay?”, and completely forgot that Cindy was in town. Or they figured it was a bit too misogynistic and went a completely different direction. XD