Her reasons for being a prostitute are all too real.... women needing money, for whatever reason (usually addiction) or to earn money for another party they feel compelled to support or are trapped in supporting (usually a man..usually a partner, but no uncommonly a father or brother), is all too real of a scenario.
It was handled reasonably deftly, though the idea of the MC going full instant White Knight, is pretty cliche, and the damage Chika displays is seems to be WAY less than is likely.. though not as bad as it becomes as when such women deny it, move past it, and embrace and accept what they do as if they the same as women who have have options, but choose that life (and YES, THERE ARE women like that).
If you cannot accept it, and feel so strongly about it... I suspect it is because you liked Chika, she is a character you felt appreciation for, or even connection to, and then the revelation betrayed that.
In that case, YOU are exactly the kind of Fair Weather Friend, the kind of judgemental fickle person,which she speaks about, which has left her so Jaded. That is ON YOU. Not the Dev.
If you cannot accept that is who she is, and refuse to play more, then you are also someone who would like abandon her if she was a real girl you met and initially liked, irl. That say a whole lot more about YOU than the Dev.
TBH, I strongly suspect you are not even someone old enough to be playing this game, given the sheltered, simplistic nature of your comment.