Folks, I am a total newbie here.  I know what the letters mean, but what is typically involved in a full body sensual massage?  Sometimes the providers talk about a happy ending and sometimes they don't.

Full Body Sensual Massage.  NEVER assume full service when a provider advertises herself as offering FBSM.

I never expected FS, I just was curious what is sensual about it?  Are the nude?  I know I am being dense.

Although if you repeat you often get more, it varies from a simple massage with you nude, while she is clothed (or in bra and panties) and you make get the chance to be upsold for a hand release; at the other end, some providers use uit as a front not to advertise GFE, but once in the session if they are comfortable you may get GFE.  This is an area where it is best to take a 30 minute option for the first visit, then if you get at least a hand release and she is comfortable with you, you can ask if more is available on future visits (that's when you take the hour and pay more).

if there is an upsell for that, then I think you're being ripped off.

Anything beyond that would be extra, including, usually any undressing on the part of the provider.

Some massage practicioners make a point that there is nothing beyond the happy ending, but you never know.

I've seen some gals like that and after a number of appointments, they were amenable to just about anything including FS.

Consider it a box of chocolates, in the Forest Gump sense.  YMMV is the operative rule.