A whole hand, by agreement
At its fullest, lesbian fisting means a whole hand inside a partner's pussy or ass, and it stops wherever the woman receiving wants it to. She sets the depth and the stopping point, and a partner who knows the act watches her breathing more closely than her own wrist.
Shaping the hand
The hand goes in shaped like a beak: fingertips pressed together, thumb folded under the palm, knuckles as the widest point. Thick lube coats the hand and her, with more added as soon as skin drags. Inside, the hand curls into a loose fist and rocks rather than thrusts. A tongue helps the muscles let go, so oral on her clit keeps going during the fisting.
Gloves on, nails short
Nitrile gloves and short nails are standard, because a hand that fits also has to be smooth. The anal version needs more stretching and grows out of fingers and toys in the ass. A gloved hand and a bottle of lube belong to lesbian fisting as much as the fist itself.
