How does Roo pass as 15??

Roo is gorgeous of course, but I’m genuinely confused as to how these men think she’s actually 15. I know how many young women are starting to look older even in high school to where I wouldn’t even notice they are underage (I’m 25, female, and a bartender for context so I mostly have a great eye for guessing people’s ages but I’m just saying these days its growing increasingly hard to tell). That being said, I know I may be a harsh critic since I’m a bartender and guess people’s ages more often than most, but could people offer some insight to this? I could understand Roo trying to pass as a 28-31 year old and I would believe it, but 15 is puberty age and it’s 25 years her junior. In addition to this, I thought the predator’s whole deal was fetishizing young women because they aren’t fully developed (otherwise why wouldn’t they just try to get a 20 yr old for example, still very young but physically developed and no legal issues). Roo’s fully developed all around so it’s confusing why these men would go for her even if she was 15 because she looks in her twenties anyways? I’m really not understanding, are these men really just that dumb or what is it about Roo that you think is allowing her to pass for 15? Thanks for any insight