How To Bring Up The Subject Of Tying Your Girlfriend Up During Sex

I'd like to tie my girlfriend up during sex, how do I bring up the subject?

Bringing up the subject of wanting to tie up your partner, particularly if it's a man wanting to tie up a woman, is something where you perhaps need to know the person pretty well. Introduce the idea in conversation: Would she mind it? What would she find acceptable? Would she find it exciting? If she wouldn't find it exciting at all, don't go any further with it. If she's prepared to give it a try, great! Don't be extreme, don't go for the full tying up with extreme knots and stuff like that - just a little bit of her hands or the feet, and for a very short period of time, just to give a feeling of it. Gently is the idea, and get permission all the way.