Sex in any water is quite dangerous for the woman, because the water can be pushed up into the uterus, which can cause a major infection. Spermicide is affected by water, but that may be the least of your problems. I believe Latex would hold up under water, but I may be wrong. If you use a different make of condoms, because of a latex allergy, I would not suggest water sex. Anal sex in the shower, however, feels awesome. If you can talk your girl into that, that would be the best option. Especially since the shower is a relaxing place, and she would more accepting of ur cawk in her azz.