It can be a kink thing, or a general health thing too. Go to an AMP that offers it and try it out.
Went to one for a massage, and a hand release "happy ending"... the place I went to didn't offer oral or FS... so she oiled up her hands, and started stroking me, then used her other finger to slip it into me, until I started shooting ropes, which is something I haven't seen myself do since my younger years... never felt so relaxed and drained afterwards... so I usually request it to whichever AMP that offers it.
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