@momozzz
You can youtube search for videos of Okubo Park. Here is an example:
https://www.youtube.com/watch?v=95NO6rRRql8. Most of the girls that are standing around with their phones out are apparently working girls. Seems like it's an open market kind of thing with likely varying services offered depending on the girl. While enticing tbh I doubt chance of getting anything from these girls unless you are Japanese, or are Asian and can speak some Japanese.
If anyone else has knowledge on these girls I would love to see if there's a way in for us Gaijin homies lmao.