Qur'an 24:34 "Force not your slave-girls to whoredom (prostitution) if they desire chastity, that you may seek enjoyment of this life. But if anyone forces them, then after such compulsion, Allah is oft-forgiving."
Owning females slaves is ok, and forcing them into prostitution is ok. Besides, having sex with a slave is always ok.
Tabari IX:113 "Allah permits you to shut them in separate rooms and to beat them, but not severely. If they abstain, they have the right to food and clothing. Treat women well for they are like domestic animals and they possess nothing themselves. Allah has made the enjoyment of their bodies lawful in his Qur'an."
Only one problem with your little theory. Serbia doesn’t follow Sharia law. Serbia is Eastern Orthodox Christian and like all Christian countries, they prohibit slavery. Only Muslim countries still allow slavery.