I suppose it would depend on my day by day mood whether I would feel the need for complete privacy or not. Some lgs and femmy boys are quite voyeuristic and get very erotically turned on by seeing a man packed with libido having a really steamy intense toss-off. In any such case that I would be in the mood for privacy, I'd keep her away ONLY because the need for that privacy factor alone, NOT because of simply how OLD she is and that I'd think that her seeing or having sex is "inappropriate". If I believe in her right to actually have sex herself, then I'm hardly going to worry about what she thinks if she just SEES sexual acts.