... Im still trying to figure out why many girls request that men be clean, drugfree, and generous. The two former are obvious, but Im foggy on the generous part. Is there some protocol that dictates a client tip a certain amount or percentage above their set rates ? In leu of money, would flowers or a bottle of nice perfume be out of the question ?

NO Play is the only safe assured thing, but if your going to play,take the neccasary precautions. Life is kinda funny that way. But here are the facts on all this wether you see a TS or a GG, Provider or a non provider.
Kissing, not to much can spread that way other than maybe clamidia, or a nasty cold? (Ok maybe a few stupid germs too
                                                  )              First the bad news, about anal types of contact. You should be aware of Hepatitis A and B. And any hep is dangerous obviusly.

Now the good news..........You can limit (if not elliminate) the risk of Hep A and Hep B, by simply getting vacinated against it at any clinic. It's inexspensive insurance, and if you do keep things in prospective.........such as just using your big head it will stave off bad things in your future.
Like I said it doe's not matter if your Gay/Straight/BI or even an  alien, just play smart! (there you go........The game of life)