Originally Posted by Mandy
A half hour?! I must just be a horny bitch then.
God bless horny bitches.
As for the original question, what devine says is right.
I find it relatively easy to keep an erection after the first orgasm because the head of my penis is hyper-sensitive. Most of the time, I can keep it in, move it around and continue. Of course, this is very risky if you're wearing a condom as the only means of birth control, but if you don't let your big head deflate your little head, you should be able to remain hard.
Also...try different positions. I find that when I'm on my back, I can go forever.