GR translation: squeak-stockinged

[Mike Jing]

P171.13-24   Sometime during the annual PISCES Christmas Party,
Pointsman is led by Maudie Chilkes to a closet full of belladonna,
gauze, thistle tubes, and the scent of surgical rubber, where in a
flash she’s down on her red knees, unbuttoning his trousers, as he,
confused, good God, strokes her hair, clumsily shaking much of it
loose from its wine-colored ribbon—here what’s this, an actual, slick
and crimson, hot, squeak-stockinged slavegirl “gam” yes right among
these winter-pale clinical halls, with the distant gramophone playing
rumba music, basses, woodblocks, wearied blown sheets of tropic string
cadences audible as everyone dances back there on the uncar-peted
floors, and the old Palladian shell, conch of a thousand rooms, gives,
resonates, shifting stresses along walls and joists . . .

What is "squeak-stockinged" exactly?