Cartoons are often thought of as kid's stuff, Saturday morning fare that couldn't possibly offend. But all mediums eventually attract subversive artists willing to buck trends. Comic books were put on trial in the '50s for that reason. Animated movies have proven to be no different.

Animated blood, sex, nudity, drug use. Many of these animated films that are definitely not for kids date back to the 1970s, when R. Crumb and other counterculture cartoonists were doing radically important work. Ralph Bakshi and other filmmakers followed suit, redefining the limits of what it was acceptable to animate.

And then there's animation from abroad. In Japan, for instance, norms about who consumes cartoons are different. That country's artists have been pushing the limits since that painting of the woman in congress with an octopus.

Get familiar with these 25 cartoons that aren't for children.

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Written by Rich Knight (@)