It's estimated one in fifteen American men 18-24 has committed rape, so at any given time, there's far, far more likely to be a rapist in your audience than a murderer.
This is important because of what each tells themself: in one case, "it wasn't really rape," in the other, "s/he needed killing." Being corruptions of the two most common legitimate (affirmative) defenses - consent and justification, respectively - these are essentially the same defense. Both of them are reinforced by trivializing the matter in the form of jokes - nonconsenting victims who aren't really violated because they're only figures of fun, and unjustified homicides that aren't murder because of a patently absurd justification. In both cases, most of the audience recognize the absurdity of seeking to so minimize a real crime, but the way the human mind works, those who are already so inclined might seek to minimize the guilt of their inclination (or even the actual fact), and there the symmetry breaks down. Because while the uncaught murderer who might be reading your strip is too rare to be worth worrying about, and knows he has no friends, the sizable minority that is the rapists in your audience might see a hand reaching out, to assuage their fears, to steel them to offend again, or worse, for the first time.