Personally I draw the line when it relates to anything that can put your ass in jail.
Not a Damn thing funny with including children under the age of 18 in any meme or discussion that has to do with rape, sex or masturbation. For fuck sakes talk about anything you want but please stop with that shit. And stop making excuses and comparing it to everything else. That is on its own level.
So a rape joke over the age of 18 is somehow morally better? Rape period is illegal and morally wrong. And is the rape of a woman somehow worse than beastislity which is basically animal rape when a dog joke comes up. How about gay rape? How about muppet rape when two fictional puppets make a rape joke. You personally draw the line at under 18. Someone else may draw the line at any joke pertaining to rape. So who is right? Nobody....Nobody is right, nobody is wrong, it's a personal opinion. And be trouble with personal they vary wildly. I am not defending anyone, or condoning anything. I am simply trying to show that what you find morally objectionable may not be to another person.
Porn is a classic example this scale. The fetishes that human beings have vary wildly. What one person likes another may find repulsively disgusting. You can go on pornhub right now and find everything from sensual "making love" porn. All the way out to hardcore BDSM electro shock genatil torture. Everything from a standard blond giving a blowjob, to a blond getting her mouth shit in. It's all there buddy. To include daddy daughter roleplay incest fantasy in ultra HD. Theres even chicks strapping lifesize horse dildos to stuffed animals.
People are fucking weird buddy. And that weirdness has a huge range. Humor is also vastly subjective. I don't personally want to see some chick fucking a huge horse kock strapped to a stuffed animal. But I'm not gonna judge a guy and say that hes fucked up because he does. And the reason I am not going to cast that judgment is because I am sure there's plenty of shit that someone else can say is fucked up that I like. Even if what I like is way down on the scale, let's just say that it's simple blowjob porn. There are plenty of people in this world who think that is morally disgusting. So I'm not going to sit here and judge some guy who likes chicks eating shit porn, knowing there are millions of people out there who feel the same way about me liking blowjob porn.
Humor is the same. What I find morally offensive, you may find funny. What you find funny, I may find morally offense. And we have every right to either find it funny or offensive. What we do not have the right to do is tell someone else what they find funny is wrong and they shouldn't do that because we dont like it. To you that's a rape meme, to someone else that may be a racist meme, or a disability meme, or a making fun of a fat person, all the way down to anything that isn't wholesomly Christian, that too could offend an atheist. Nobody is wrong.