I'd love to think the masseuse gets horny like that after she does *me*! I've never seen one masturbating but I did have one girl make an obvious display of wiping her crotch with a towel after finishing me, and saying she was wet! Very surprising. And another one let me rub my dick on her pussy and then gestured to get on top of her and I slipped it inside and soon came that way!! No extra charge. Later I asked her out... haha. Two of my best memories of the dozens I've had without such "extras". Other times they won't even let me touch their titties - just their ass.
Mmm, that masseuse seems to know what she's doing. I get this kind of massage 2 or 3 times a year and I'm way overdue! Stroking and wishing it were me...