Hey guys, anyone used services off of La Rambla. Street prostitution isn't usually my thing but I did see some gorgeous Colombian girls there the last time and wanted to know if it's worth a punt?

Do they take you to a special room? Is it dangerous?

I'm completely naive to this particular scene (street) and all I can find on the web is that prostitution happens on La Rambla, not 'how' it happens.

if I were you I'd stay clear of La Rambla.
Nexus point for all sorts of crime against tourists.
If you don't know the city there is a high probability you are going to get ripped off (possibly worse). A few spectacularly dodgy areas a mere street or two off the main drag. You do not want to be on your own there (esp. late at night/early morning).
Just my opinion but LR is vastly over-rated (and ovrr priced).
For street girls maybe try streets around La Barceloneta.
Alternatively a little research on Google would provide you with alternatives like this
https://okescorts.com/en/natalia-escort-barcelona/

Happy hunting.

Bona sort!