Inflatable sex toys
From Voyeurweb's Wiki about Sex
Inflatable sex toys are sex toys, which can be inflated as a whole or have inflatable parts.
Inflatable Cushion

Inflatable cushion type sex toys have a vibrator or dildo attached to some kind of inflatable cushion or inflatable ball. The idea is to "ride" the penis shaped toy while bouncing on the cushion or ball.
Some cushions are pillow shaped and some are people shaped.
Inflatable dildo

Inflatable dildos gain more volume and increase in size when inflated. They are usually used as ass plugs and pumped up after anal insertion.