What you get when you try to sit on a toilet with its seat raised, and so you end up falling into the bowl and getting your butt wet with dirty toilet water.
Damn it! You forgot to lower the toilet seat when you were finished! Now I've caught the wet butt disease!
euphemism for exhausted, tired on every level, as beaten down as one can be. Origin: Dobbins Family saying created by Hale Dobbins, deceased, of Arkansas
The phrase "I make you wet in the butt" means some one is really hot/sexy and you feel a tingling sensation in your butt while also feeling like it's moist.