Let it be known here on out, I was not planning on bringing any toys or nipple clamps or ball stretchers or electrodes + TENS units or anything like that. A bottle of lube perhaps if chim's feeling lucky but that's about it.
It's all your dirty minds that are talking about all this stuff. Not me.
Kiki would be better at answering this than myself, but I'll give it a whirl.
The buttplug is used for many different concepts; dominating, anal training, the feeling of being in public and no one knows but you, etc.
Using a butt plug is neat because you start out small and increase the size slowly until you get to a size that you are comfortable with, ex. partners penis. This apparatus comes in a zillion of different sizes too.
I'm in class and feel uncomfortable doing this right now. Maybe I'll get into more detail when I get home.