I think not. How can there be anything else, if there’s Dr. McNinja?

From the About page:

Q: What kind of doctor is he anyway? That’s a PhD on his wall. The sign in front of his office says he’s a physician. In the one comic he’s doing dental work on a patient, and then says he’s a podiatrist!

A: Ninjas are mysterious in their ways. Way mysterious.

I love it.