Under the showerhead
Lesbian shower sex runs on water and soap. Body wash lets hands glide where dry skin would catch, wet hair hangs heavy down the back, and with no clothes to take off, washing a partner's breasts and back counts as foreplay.
Tile changes the positions
A wet floor is slippery, so the sex stays upright or low: one foot on the tub edge, a palm flat on the wall, a partner kneeling on a bath mat. A handheld showerhead aimed between the legs does the job of fingers, and a suction-cup dildo sticks to smooth tile at any height. Water rinses water-based lube away, so silicone lube is the kind that lasts.
Glass doors and steam
In a lesbian shower pairing the camera works through the glass door, and steam fogs the lens within minutes. A lesbian bath trades the spray for bubbles and a tub edge to sit on. Kissing under the spray means water in the mouth and eyes shut. A walk-in stall fits two women with room to kneel; a bathtub fits two in theory.
