Years ago I tried to get a Hotmail account with my real name and had the same experience because of Cumming. Instead I signed up for a Hotmail address with the name Ivana Watch-Teens-Give-Head.
A lot of people really would find that sentence less offensive than "I jacked off in the shower" or "Fuck, you're awesome" simply due to the more decorous phrasing. The fact that your example describes bestiality and my second example is actually an ecstatic compliment doesn't matter to such people — the phrasing itself is what offends them, not the content of the idea.