Is working in an internet cafe, where most patrons commit violations of Islamic law, such as listening to lewd songs and chatting with non-mahram men, permissible or forbidden?

If the job involves providing assistance to women who use the internet for haram (definition) (forbidden) activities, then it is not permissible to work in this cafe, because it falls under aiding in sin, which is prohibited by Allah's saying: "And do not cooperate in sin and aggression." However, if the work is not directly related to the reprehensible act, then there is no objection to it. Nevertheless, it is obligatory to advise these girls and explain Allah's ruling to them.