Lately I've been cruising up and down the aisles of my public library almost every day, because the library is a good place to go and do important research of a critical, academic nature. It's also a good place to forage for manga that I'm vaguely curious about, but not quite convinced to buy. Most libraries won't just stock any old manga, however. They're often governed by small and inflexible budgets, and can only rapidly stock stuff like New York Times bestsellers. Fortunately, Monster Musume is a #1 New York Times bestseller, and while it wasn't in stock at my library, I was able to arrange inter-library loans and start reading this surprise hit series.

On my last visit, there was a volume of Okayado's popular sex comedy waiting for me in the stacks. I also took the opportunity to grab a copy of the 3-disc MISTER MAGOO THEATRICAL CARTOONS DVD collection and had the librarian check out both items for me, because this is America, dammit. The thing is, I'm not reading Monster Musume simply because it's enjoyable (it often is) or because it's popular (it definitely is). I've been following it because it's emerged as the leader in a peculiar little boom—a boom of anime and manga about monster girls.

On its face, the idea of girls with monstrous features—leathery wings, fangs, furry ears, reptilian tails, or other animal or supernatural characteristics—is old hat to anime and manga. That sort of imagery goes back to the dawn of the medium, and more specifically, you can trace it back to late 70s/early 80s fare like Star of Cottonland (a film that features what is probably the first anime catgirl, at least as we now know them) and Osamu Tezuka's telefilm Bagi. The current monster boomlet has traced a jagged line from these early looks at the idea, but it's really taken off thanks to the hard work of folks like Okayado, the pen name of manga artist Takemaru Inui. Okayado certainly seems to be the prime mover of this emerging subgenre. One look at Monster Musume, Okayado's chart-topping hit, makes it obvious why it's so popular. It's filthy!

Granted, the series steers clear of actual explicit sexual content, but only barely—it's still steamy enough that bookstore copies of it routinely come packaged in shrinkwrap. The manga's prurient nature is less surprising when you examine its origins; the artist has worked on hentai manga, and several years back he turned out a long-running, occasional series of one-page vignettes about a dude's bedroom escapades with a variety of nominally humanoid beast-ladies like centaurs, mermaids, and slime monsters(?!). His Monster Musume, presenting us with the slightly less alarming prospect of a nice dude forced to welcome a procession of disarmingly attractive monster girls into his household, is a natural attempt to take a popular smutfest and transform it into something with more mainstream potential. Hey, starting with pornography and then walking it back to a more socially acceptable level is what gave us stuff like Project A-Ko and Fate/Stay Night, after all!

In Monster Musume's world, young go-getter Kimihito, whose face is almost always carefully blank (so you can more easily substitute yours!), takes care of the family house while his parents hide out from the Yakuza in an undisclosed location. (The story insists they're “overseas on business,” but I ain't buying it.) Enter mysterious government operative Ms. Smith, who informs Kimihito that he's been selected as the host for a liminal—a lady from the monster world, stuck halfway between beast and human. It all leads to him waking up next to Miia, a charming and disconcertingly possessive lamia—a snake girl. It's up to Kimihito to welcome her to ordinary human society, as if she's an exchange student, all while learning how to cook, clean up after her (she sheds her skin, just like a snake!), and otherwise be a good host.

This is a harem series, so the endless procession of additional monster girl houseguests begins apace as soon as Miia settles in. We meet the harpy Papi, a literal bird-brain; centaur Cerea, who is modest and talks like Thor from the old comic books; Suu, a slime monster (?!?); and my favorite, Mero, a mermaid princess who takes great joy in sabotaging her own life, in order for her to imagine herself as a tragic heroine. These cutie-pies all have two things in common—they all find themselves crushing on their new host, and they all end up at least half-naked all the time, and bingo , now you know why this series is so explosively popular!

The thing is, smutty content might be good enough to get a series noticed, but it's not as likely to make it into a sustained hit. And after reading a couple of volumes of Monster Musume, the genius of the series makes itself apparent. Okayado isn't merely good at drawing comely girls with scales and tails—he's very inventive, and just when you think the flood of charmingly weird monster ladies is about to dry up, he introduces a few more. We meet a zombie, and a cyclops, and an ogre, and a wood nymph, and a lizard lady, and a kobold straight out of the old AD&D manual. We even get to watch Kimihito try to help out a dullahan, a mythical harbinger of doom whose head and body can separate and act independently. If you've seen Durarara! , you've encountered a kinda-similar character, but for me, the dullahan will always be one of these dudes from the Shining Force games.

I don't know how the hell he does it, but Okayado manages to pull off a cute and sexy dullahan in the pages of his manga. And of course, his protagonist Kimihito is really just a good man who just wants to help these girls integrate with human society and live normal lives, but he somehow just keeps slipping on banana peels and falling straight into their boobs, leading to a nonstop parade of gags, misunderstandings, and lewdly inadvertent near-sex-acts. This popular manga naturally spawned a popular anime, but I only tuned in long enough to verify that it maintains enough of the charm of the original to be censored for its initial TV run, the better to sell you uncensored Blu-rays a little further down the road. I don't mind this approach (Prison School's anime version has gone the same way, and both are just a couple of the latest in a long line of salacious cartoons that conceal the goodies with convenient cropping and shafts of impenetrable, heavenly light to tempt you into buying the home video version) but that kind of thing will keep me from tuning in until the uncensored version is available.

Even as Monster Musume aired last July, it was joined on the airwaves by another only slightly less monsteriffic cartoon, the somewhat clumsily-named Actually, I Am. The title is actually really apt, and one that's cleverly used by the characters over and over again. Protagonist Asahi seems like a good, well-adjusted young man, but actually he's utterly incapable of keeping his opinions and secrets to himself, or telling lies. He discovers, as he rushes to confess his feelings to his latest crush (trying to hold back is no good, because of his terrible poker face), that she's actually a monster—in this case, a vampire. Another classmate is actually a teenaged werewolf—a teen wolf, if you will. Even the stuffed shirt of a class representative (his old crush, who'd flatly called him out and turned him down) is actually something otherworldly; her true form is revealed in an abrupt and hilarious sight gag that I won't spoil here.

Most of the rest of the series characters are broad walking stereotypes, but as a sitcom, Actually I Am works pretty well, because its protagonist has something that Monster Musume's Kimihito doesn't—a personality! The big twist, in this case, comes when he tries to tell the vampire, Yoko, that he likes her—his wording is a little too vague, but his buoyant, hopeful “Let's be friends!” speech is delivered with such conviction that she's blown away and immediately agrees to be platonic buddies. Yoko's rattled by her vampiric secret being known by the guy who can't keep a single secret, but Asahi promises to help her lay low and integrate with human society.

This is a series that's a bit lower on the monster content than Monster Musume, but I immediately lump it in, in no small part because of the English-language title that manga publisher Seven Seas has chosen for it, My Monster Secret. I haven't read the manga yet—I've got volume one on request at the library!—but the new moniker strikes me as both a shrewd piece of marketing and an undeniably better title. Yet another monster girl manga I've been reading from Seven Seas is a gentle, domestic tale of an ordinary young girl with the lower body of a horse called A Centaur's Life. See, here's the deal with the whole monster girl phenomenon—it's not enough to merely create a cute girl character with horns, or a mermaid tail, or a spidery carapace, or other animal characteristics. Artists like Johji Manable have been doing that for decades. You could even argue that good old Lum, with her horns and alien origin, is something of a monster girl. What sets this genre apart is the “daily life” element, the notion of having the monster girls do completely mundane things like housework, a day job, going on dates with ordinary guys, or heading off to school. That's A Centaur's Life's game, with one interesting twist.

In this manga series by Kei Murayama (originally title: A Centaur's Worries), the reader is presented with an elaborately-constructed parallel world where the human race has long since vanished, gone the way of the ancient cro-magnons, making way for a different kind of human society—one populated with centaurs, satyrs, mermaids, angels, and of course, lizard people. Main character Himeno is a high school girl in this world, just trying to get through her day with the help of her buddies, Nozomi and Kyoko. The series immerses itself in both school and family life, as its characters take turns navigating the pitfalls of high school and helping raise their cute younger relatives.

A Centaur's Life is a series that would end up feeling a bit mundane if not for Murayama's gentle stories, detailed descriptions of the story's larger world, and most of all the breathtaking artwork, which is very delicate and attractive. Himeno is a charmingly shy character, and very close to her friends and family. In a lot of ways, what's presented here is a very straightforward story of the excitement and confusion of adolescence, only with the centaur thing tossed into the middle of the ring to keep it interesting. And Murayama really does keep it interesting—amongst the bustle of daily life, he answers questions like: How do centaurs bathe and get dressed in the morning? What do they eat? How do they go to the toilet? Questions like these might seem kinda goofy and superfluous, but I found myself thinking about them often while reading Monster Musume (for example: is Miia a total carnivore, with nothing but meat in her diet? Man, she must take the worst shits ever!), which doesn't make quite the same effort to answer them.

You might be noticing that all of these monster comics seem to be coming from the same publisher. That's no accident—in Japan, most of them run in the same magazine, Monthly Comic Ryu. In that way, you could say that the monster girl fad is kind of an artificial trend, one pushed by the magazine. But the fact is, they're doing a pretty good job of it, because none of their titles really feel trite. One glance at the cover of Nurse Hitomi's Monster Infirmary had me thinking that this was going to be the one, the knockoff that exposes how facile the whole monster girl thing really is. In fact, it turns out to be better than its predecessor, because it does such a fine job of focusing on the comedy over the raunchiness.

At Nurse Hitomi's school, both boys and girls have monster characteristics, and when they get bumps and bruises or aren't feeling well, it's up to the school nurse to cure what ails them, even as her monoscopic vision (as you can see, she's a cyclops) causes her to struggle with poor depth perception and adorably trip over stuff. In the comic's opening story, a girl comes to the infirmary, because she's confused and worried about what a boy in class might think of her. See, her body is going through all of these changes , particularly her tongue, which has grown astonishingly long and articulated. Later, Hitomi will be tasked with helping other kids adjust to their growing bodies, like a giantess who's getting too big for practically everything at school, and her best buddy, a sprite who's going through a shrinking spurt.

As you can probably tell, this series works because artist Shake-O (I enjoy these pseudonyms, man. I wish they'd catch on in western comics, so I could read Spider-Man by Ed Brubaker and STOMP) cleverly takes ordinary teenage concerns and dresses them up with monster-y characteristics. The series also works because of its protagonist, Hitomi. Her clumsiness is played as a gag, but she's a good mentor to the kids, and also weirdly cute, in spite of (or possibly because of…?) her one horrible eye. One fun thing to do is to compare her to the cyclops girl in Monster Musume, who has one eye but two eyebrows for some reason.

If you're digging these monster comics, there's more where they came from on the horizon, such as I ♥ Monster Girls (a gag comic set in the world of Monster Musume), and Monster Girl Encyclopedia, which is exactly what it sounds like. One thing I've been doing lately is craning my neck to try and spot the monster girl boomlet's influence on other manga and anime—and I've noticed that my favorite character in Kohei Horikoshi's superb Shonen Jump hit My Hero Academia is Tsuyu, a superheroine with froggy characteristics that was almost certainly developed in response to the whole monster girl emergence.

Going forward, I'm sure it's only a matter of time before we get additional hits like My Monster Coffee Shop, Monster Political Debate, and The Monster Girl Laws of Divorce and Inheritance. I'd be willing to give any of these a shot, and not just because I could probably turn them up at the library. I find these monster girl comics charming more often than not, because in spite of the weird, almost omnipresent fanservice (even the comparatively chaste, understated A Centaur's Life has a couple of bath scenes), they tend to be all about the importance of making friends and living harmoniously together with a variety of very different people. That's a message that's important and effective no matter how many fangs, bat wings, scales, gills, feathers, and pointy animal ears you tack onto it.

Would you really want a monster girlfriend or boyfriend? Did you watch Monster Musume as it came out, or are you waiting for the uncensored version to hit home video, so you don't have to watch it twice? Have you been buying the manga, or just furtively trying to slide the shrinkwrap off at the bookstore and sample it there? (I always notice that there's at least one Monster Musume volume at the bookstore missing the shrinkwrap…) Are there other monster girl comics and animation worth checking out? Share your thoughts in the comments!