Know descendents of the wicked witch of the east (or was it west) do. Some in the GBF have to be. That is having a little wickedness in their family tree. That's the only way that explains them ;).
*Guess it is theoretically possible being allergic to water. Don't see how considering how much the body consist of it. Never actually looked into it. The Wikipedia page is very vague of it too. Wonder how much medical studies looked into it.
Sounds more like a skin problem than a true allergy? I mean you can't survive without intake of water, and if you truly were allergic to it, it would affect your insides as well as your skin. Have you seen a skin specialist?
If you seriously think you're allergic to water then you need to have a consultation with a real medical professional such as a real physician. You need to find out what it is in the water you consume that you're allegedly allergic to. Water is pure; the additives to it to make it taste good or make it purer are not.