Contrary to popular belief, anime is not just for kids. In fact, there are a lot of mature themes in anime you need to be an adult to understand. So, how did we end up with the idea that anime isn't for adults? Maybe it's because in the Western world, animation is almost always aimed at children.
For some, the link between animation and kids' media is so powerful that a lot of American kids grew up watching totally inappropriate shows like Family Guy, Ren & Stimpy, or South Park. Their parents assumed that if it was animated, it must be kid-friendly. It could also be because the anime that gets imported over to the West tends to be aimed at kids. Anime-loving millennials grew up on Pokémon, Digimon, Sailor Moon, and DBZ. These series were also heavily censored in the dubbing process, making these already kid-oriented anime seem even more childish.
Animation in Japan isn't all Digimon and DBZ. There's plenty of anime for grown-ups out there. From sexual anime to series that feature drug abuse, some anime ask serious moral questions. In fact, a lot of what's on offer simply isn't appropriate for kids. So, if you're post-college and you're still into anime, don't worry. It's totally appropriate, and there are plenty of reasons anime is not just for kids.
While shows aimed at kids might make the occasional thinly veiled sex joke, they typically don't go beyond acknowledging that sex exists. They certainly don't show the act in question. While there's plenty of adult-oriented anime that can be viewed in polite company, some of it is better suited to... private viewing.
Some sexually explicit anime is ridiculous. For example, it's supposed to be super hot when some dude brushes his younger sister's teeth in Nisemonogatari. Some scenes depict the beautiful coming together of two people who love each other, though to be fair those scenes often fade-to-black. Some sex scenes are depressing. For that particular poison, check out the heart-stoppingly miserable sex that characterizes Scum's Wish. Some is disturbing, which you'll have noticed if you ever watched Berserk. Some is just straight-up erotic, and that happens more often than not. Obviously, none of it is even remotely child-appropriate.
There's no way to discuss complex moral decisions in anime without mentioning Death Note, so let's start there. For the uninitiated, Death Note focuses on Light Yagami, who finds a magical notebook that kills anyone whose name is written inside. He decides to use this notebook to kill criminals and improve society. Eventually, a combination of hubris and desperate attempts to avoid capture lead him to betray his original morals. Kids who watch Death Note tend to focus on how badass they think either Light or his detective opponent L are. Yes, L is badass (Light isn't, sorry guys) but the biggest hook for grown-up viewers is the major question posed by the series: does any one person truly have the right to decide who lives and who dies?
Death Note is a classic example of an anime that poses moral questions, but it's far from the only one. Another good one is Psycho Pass, which features the Sybil system, a series of tests that analyze your personality, your mental and physical health, your genetic heritage, and other traits to determine your station in life. Viewers of Psycho Pass have to grapple with the concept of free will. What does it mean? Is it real? Are our choices actually determined by traits we don't control? How does free will factor into the creation of an ideal society? These are not questions targeted at kids.
The kinds of food we choose to put into our bodies is actually a pretty serious issue, and not just in terms of our personal health. How far will we go to ensure our own survival? What about our own personal happiness? What kind of consumption makes you a monster? These aren't issues kids are necessarily ready to consider.
That said, there are some really interesting adult-oriented anime out there ask these kinds of questions. Tokyo Ghoul, which is explicitly violent enough to disqualify itself as a kids' show already, is one example. "Ghouls" are humanoid creatures who cannot survive without eating human flesh. Often, this means being forced to take human lives. As viewers watch Kaneki, who has been surgically transformed into a ghoul against his will, struggle to accept his survival needs, we have to ask: is it really wrong for ghouls to kill? Is it different from humans killing cows, chickens, and other animals for our own survival?
On the flip side of this, we have The Eccentric Family, an anime about the conflict between humans and mythical creatures called tanuki and tengu. The tanuki patriarch of the Shimogamo family, Soichiro, was eaten alive by a group called the Friday Fellows. To the tanuki characters, this is terrifying, but to the humans, it's a joyful tradition that brings them together and gives them the chance to appreciate a unique food. Whose perspective is right? Can both be? Is consumption appreciation? If you love something and destroy it, is that still love?
There questions aren't easy to answer, and The Eccentric Family doesn't attempt to do so definitively. Like Tokyo Ghoul, it forces viewers to think seriously about their own food choices in a way that's unlikely to resonate with most kids.
Revenge is a concept that pops up frequently in anime, and it's not exactly a kid-friendly idea. Especially when that revenge involves copious amounts of blood, as it often does in anime. Anime with more mature themes can actually question whether or not revenge has value.
One of the most interesting examples is Scar from Fullmetal Alchemist: Brotherhood. Scar is one of the few survivors of a genocidal attack on his people, the Ishvalans. Understandably, he wants revenge on state alchemists, who are largely responsible for murdering his people. Two of the alchemists that he kills in his quest for revenge are Winry Rockbell's parents, which sparks a desire for revenge in Winry herself. Scar tells her that while she has the right to kill him for what he did to her parents, he will consider her an enemy if she does, and the cycle of hatred will continue. The series questions the purpose of revenge. Does it make anything better, or does it just create new problems and exacerbate old ones? Can things like genocide actually be forgiven? If so, how? If not, is revenge the only way to handle it?
Of course, FMA isn't the only series where this concept comes up. We all know about Sasuke Uchiha's quest to kill his brother Itachi for murdering their entire clan in Naruto. Sasuke only finds out the terrible circumstances behind his brother's actions after he's already killed him. Once he finds out that Itachi was forced into the mass murder by a corrupt government leader named Danzo, and that Itachi's actions were the only thing that saved Sasuke's own life, his revenge feels hollow and meaningless. Naruto and FMA are both billed as kids' shows, but there are plenty of adult ideas about revenge to unpack.