Are you a creep for writing about a toilet-licking monster? I doubt it. I don’t think Nabokov was a creep for writing Lolita, nor was Thomas Pynchon a creep for writing the extremely detailed scene in Gravity’s Rainbow in which a man eats excrement. True, people have had visceral reactions to both the authors and their subject matter, but that’s to be expected. As a fiction writer, you do your job primarily by telling compelling stories using images, characters, and motivations that give your readers something new and delicious.
In the long run, your reputation as a writer will likely hinge on several things: quality prose, excellent storytelling, memorable characters, unforgettable scenes, and consistency. You might consider approaching your concern from the consumer's point of view: readers desire a “certain something” from a genre work, and they gravitate towards the writers most likely to provide that certain something. They are looking for something general, rather than something specific, i.e. they want to be terrified or grossed out, but they aren’t specifically looking for toilet-licking monsters. You’re pretty safe on that count. If you can add humor into the mix, even better.
That being said, and more specific to your question, certain aspects of your writing can become “trademarks”, so to speak. David Cronenberg (director) writes/directs films “about" body horror; Shirley Jackson writes psychological horror (and I doubt either of them would appreciate being labeled this way). However, I suspect that “trademarks" of writing only become trademarks over time. Perhaps a counter-arguement is Bret Easton Ellis, whose American Psycho was so shocking that he himself came under scrutiny (this NYTImes article from 1991 is a fun place to start).
Ultimately, I suspect that many readers have a maturity level that can handle the gross out details. On the other hand, if your primary readers are presently friends and family, be prepared to get some questioning glances at Thanksgiving.
