Guangzhou - city of action. But you must be very very careful. Pick pockets everywhere. do not leave any bags unattended. especially at train stations, etc. they work in groups.
I go there every month, and the usual place to pick up are at karaokes. Usually the girl sits with you for RMB300 and then you can negotiate from then on. There are numerous massage/spas and they usually give sex packages as well.
Companions - well, you have to go more often and work on it...