For women:

Cucumber
Banana
Water with pressure
Pillow
Hairbrush
Toothbrush
Candle
Marker
Blanket
Makeup products, brush, lipstick
Bottle
Thermos
Tool handle, hammer
Remote control
Massager
Olive oil
Clothes pins
Ch1ldren toys, dolls, animals
Ice cubes
Heat pads
Hot water bottle
Coke cans
Top of bed post
Other furniture appendages
Lint roller
Frozen sausage
Vacuum cleaner
Wheels of rollerblade
Washing machine (sit on it when spinning hard)
Qtips
Round door handles
Lubed dolls
Kitchen roll holder
Bike seat
Handles of gym machines
Balls and round objects
Horse riding
Joy sticks
My tongue
My fingers
My dick
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I've masturbated hundreds of times together with women and masturbated many of them myself, so I've pretty much seen everything. Well, almost...