You might want to take a look at this: https://www.amazon.com/Adam-Eve-Motion-Rabbit-Vibrator/dp/B01N4ES1ZF
My wife got the same thing from an Athena's party and, while most everything she's brought home from them is garbage, this one hasn't ceased to amaze us. The ability to control individual motors makes it very versatile. Scale is hard to judge from the pictures, but it's relatively slender in person.
Every one of them, it just depends upon how adventurous you're feeling! Seriously though, this Adam & Eve toy is that I have tried and would recommend.