Dirty comics have been around almost as long as the medium itself. No doubt a few years after the Yellow Kid first appeared, some wiseacre created a Tijuana Bible of him getting busy with Buster Brown's mom.

Sadly, most of the sex comics produced over the years are awful, dreary affairs -- works that either feature abysmal art and writing or indulge in such ugly stereotypes (or both), so that you feel ashamed for all the people involved, including yourself for having read the thing.

But there are a few gems amidst the x-rated dross. Below are six smut-laden books that, while you may not want to be caught reading them on the bus, can proudly display on your bookshelf without embarrassment.

I had a couple of self-imposed rules with this one. First of all, the comic had to be sexually explicit. Second, it had to be primarily designed to titillate the reader, thus nixing darker, serious work like Phoebe Gloeckner's A Child's Life.

Also, I'm sure there are plenty of books I'm forgetting about (catering to my own tastes, there's a focus on heterosexual fare here), so feel free to mention your own particular favorites in the comments section. You naughty thing you.

Finally, while I've tried to keep everything below the jump relatively safe for work, I can't promise that all the links will be PG-rated, so caveat emptor.

1) Small Favors by Colleen Coover. Before she started doing kid-friendly work for Marvel, Colleen Coover made her reputation with Small Favors, a lesbian sex comic that's most notable feature is how gosh-darned cute it is. Seriously, the most amazing thing about the book is that it manages to be rather filthy and yet utterly adorable at the same time. It's the easily the most endearing porn comic you'll ever encounter. The good news is Top Shelf is planning on publishing an omnibus collection of the series, so you can feel the x-rated wuv all over again.

2) Birdland by Gilbert Hernandez. Let's be honest here. Most of Eros Comix's output has been awful to put it mildly. Not so with Birdland, one of the initial stars in the line's stable, and easily one of the most freewheeling, genuinely goofy works Beto has ever produced, which is saying something. A riotous, hardcore affair involving space aliens, time travel, magic lockets, gender bending and just about every character in the cast getting down and dirty with every other member, with little shame or bad feelings involved. Hernandez would later work many of these characters, most notably the sisters Fritz and Petra, into the main storyline of his Palomar/Luba work, with a decidedly more realistic and occasionally grimmer results. As much as I like those stories, part of me kind of prefers the carefree, upbeat versions portrayed here.

3) Maka-Maka by Kishi Torajiro. Maka-Maka is one of those rare x-rated manga that doesn't involve tentacles, rape, schoolgirls or annoying gender stereotypes. What Maka-Maka does have is even rarer: an honest, insightful portrayal of a romantic relationship, in this case between two close female friends who slowly starts to get more serious and involved over time. The irony is that they see their sexual relationship as just fun and games and continue to pursue a number of bad relationships with men even though they clearly are in love and belong together. Though it was originally serialized in a men's magazine, Maka-Maka is anything but exploitative. Indeed, it's written with a good deal of sensitivity for its characters and their relationship that makes the sex scenes all the more intense and meaningful.

4) Nipplez 'n' Tum Tum by Mary Fleener. Imagine if Betty and Veronica were more jaded, street savvy, took recreational drugs and got laid a lot more often and you have a basic idea of what Nipples 'n' Tum Tum is like. After initially appearing in the second volume of Fantagraphics Dirty Stories anthology, Fleener put out one issue starring the lusty pair through Eros Comix. It's a rather funny, sex positive affair involving rock star poseurs, lesbian drug dealers and uber-cute boys that ends with the girls getting the upper hand, as per their wont. Overall it's a really funny, smart comic filled with Fleener's great, cartoony-cubist art (especially during the more intense sex scenes; no one draws an orgasm like Fleener). One wishes she had tried to keep the comic going for awhile longer. It deserved a longer shelf life than it ultimately got.

5) Chester 5000 by Jess Fink. Notice that a lot of the comics on this list are by women? That seems to be a growing trend these days, as more and more female cartoonists have said "damn propriety" and started drawing pictures of naked people doin' it. It's a welcome trend overall, especially when the results run towards something like Fink's Chester 5000, a sweaty steampunk porn romance involving an inventor, his well-equipped robotic creation and the neglected wife who finds a new bedtime companion in the metal man. Like Small Favors and Maka-Maka, Chester manages to offer a bit of sweetness and warmth amidst all the commingling of genitals, making it an easy choice for inclusion on this list. Top Shelf (which is quickly becoming the go-to company for tasteful porn) will be offering a print collection next year.

6) XXXenophile by Phil Foglio. But of course you eventually return to the classics. After Omaha the Cat Dancer, Foglio's hot and heavy collection of short story erotica is probably one of the best known and beloved sex comics from the 80s and 90s -- or at the very least it didn't make people scrunch up their noses in disgust when they read it. Frequently delving into the realms of fantasy and sci-fi, the series won acclaim for its playful, positive attitude. Foglio has famously  said he won't do any more erotica while he's still on his kids' PTA board, but you can still get .pdf copies of the comics online (check that last link).