Does anal sex make your hips and bottom larger?

I've had one my questions answered before and I'd like to thank you for answering it because it was very useful :) Now I've got more!

• Sex with my significant other has been wonderful the past few times we've done it, emotionally. I still wonder about physical, though. I have orgasmed before but only with my own clitoral stimulation. Is there a possible way or technique used to attain vaginal orgasm?

• I've also wondered about unprotected sex...I have not done it yet, but I don't want to rush into things before something bad happens. I am on the pill and we were both virgins when we started. So I know that there is no possible risk of STD's. I heard it feels better for both partners with no condom, so what are my risks and options?

•I always thought that sex in the water was unhealthy. Then I came across a book in my local sex shoppe about how to have sex in the water! Doesn't the water ruin the latex of the condom or is it safe not to use one in the water?