How about a VN where you manage comfort women?
You're an army technical captain responsible for running a "comfort station" for the front line troops. You start out with two japanese volunteers. As the formation you attach to fight across asia you 'recruit' locals from Korea, South East asia, China and finally highly sought after European lolis from Shanghai, Hong Kong and Singapore.
To receive funding from imperial command you have to fill quotas, but work your lolis too hard and they will collapse from all the rape. Also, troops returning from harsh regions (Kokoda trail, Solomon Islands, etc) are more desperate and perpared to pay more to get priority, but are more likely to infect your lolis with venereal diseases, making them much less desirable.