One of the protagonists is a girl with a rough history, who "works" as a callgirl to keep afloat. She is a handfull, distrusting and rude BUT she is one of the characters, that make this story deep and worth the while. You CAN interact with her (wich I strongly recommend), but you don't have to. Those who judge her are, IMHO, hypocrits...
And what's hypocritical about that? Prostitution has always been the easiest way to make money, you don't need to have a special brain to do it. There's even a saying: it's better to have a thief as a son than a prostitute as a daughter. She could easily have been a webcam girl, that would have fit in since the action takes place in the modern world, but no, she sleeps with rich old men, so why should I be interested in her story (even if she has such a father, that doesn't justify anything), and if not, then I'm a hypocrite, well, well, well. Many barely survive in our world, but they don't engage in prostitution.