Superheroes are known for their pure hearts. They protect the less fortunate and act as role models for the people of their cities. They inspire citizens to be better and to fight for what's right through their heroic actions. While there have been many exceptions through the years, superheroes don't normally turn to the dark side. Sure, Batman is decidedly more inclined to do questionable things than Superman, but he usually channels his darkest tendencies through good deeds. You could almost never picture good-natured heroes like Superman, Squirrel Girl, Supergirl, Batgirl or Spider-Man (sans symbiote) doing suspicious things that would be less than inspiring to the youths of the world. Yet, all of these characters have gotten a little nasty throughout their crime fighting careers...

RELATED: 50 Shades Of May: 15 Times Aunt May Got Lucky

After all, superheroes have needs to! Comic books are full of instances when our favorite superheroes got a little hot and heavy with loved ones... or perhaps even enemies! There's at least one example of a superhero sleeping with the enemy. Oh, and did you know that one of the most famous superheroes of all time was once a star in an adult film? You might not see that one coming. This and much more in CBR's list of the goody-goody superheroes who like to get nasty:

15 SUPERMAN

Superman and Big Barda make a Porno Action Comics

Superman is perhaps the most heroic and goody-goody character on this list, yet he starred in one of the naughtiest comic book issues of all time. Action Comics #952-953, a two-part story by John Byrne starring Big Barda and Mr. Miracle featured Superman in an adult film! Almost 40 years after the release of the issue, this remains one of the most controversial Byrne Superman stories of all time.

Big Barda is captured by a villain named Sleez, a gross-looking alien dude who was banished from Apokolips for being too depraved for even Darkseid. Sleez makes her dance for him in a skimpy outfit in the sewers of Metropolis and releases video tapes of her performance. Then Sleez captures Superman and manipulates him into filming an adult scene with Barda. Just as they're about to get it on, Mr. Miracle comes crashing down on the set and saves them both.

14 ANT-MAN (HANK PYM)

Avengers 71 Hank Pym Janet deleted scene

While "the smaller the better" isn't usually the saying people use when talking about getting nasty, that is Hank Pym's strategy for pleasing his ex-wife, Janet Van Dyne (aka The Wasp), during some time off to rebuild their marriage in Las Vegas. Leave two characters with incredible shrinking powers locked in a hotel room and some very nasty shenanigans are bound to ensue. In this case, Hank uses his shrinking power to... well, visit Janet's downtown area.

It was writer Geoff Johns and artist Stephen Sadowski who thought up this particular shrinking fetish scene in Avengers Vol. 3 #71. The comic book world would never be the same again. Well, maybe that's an exaggeration, but these panels will certainly make you do a double take. There is perhaps no character nastier than Ant-Man.

13 SPIDER-MAN

Black Cat diamonds

Despite being your friendly neighborhood Spider-Man, Peter Parker has gotten around quite a bit since becoming a crime fighter. Sure, Gwen Stacy and Mary Jane Watson were actual relationships, but Spidey's had his fair share of flings. None of those were as hot and heavy as his affair with Black Cat, who has at different points been the hero's enemy and ally. At one point, they decided to date despite Black Cat's rap sheet.

Spidey was in so deep with Black Cat that he decided to show her where he lived and reveal his secret identity to her in Peter Parker, The Spectacular Spider-Man Vol. 1 #87. But instead of falling deeper for him, Black Cat is appalled by her lover's true identity and begs him to put his mask back on. She's in love with her adversary, not the regular guy from Queens.

12 SUPERGIRL

supergirl-lying-at-black-flame

In Superman Vol. 2 #16 by John Byrne, we were introduced to a new Supergirl, this time an artificially engineered woman from an alternate Earth where there was no Superman and Lex Luthor wasn't a bad guy. Her name was Matrix. While good Lex designed her to resemble his redheaded long lost love, Lana Lang, who had died in this reality, she could transform into a young blonde woman and fight crime as Supergirl.

Matrix eventually made it to our Earth and joined up with Superman, although she ended up falling in love with our Earth's evil Lex, who used her to create a bunch of clones after they started dating. The moral of the story is that if you plan to sleep with the enemy, make sure they don't plan to use your DNA for dastardly means.

11 CYCLOPS

You know Cyclops, one of the original X-Men, super in love with Jean Grey, who he's always been devoted to and has totally never had an affair behind her back. Nope... WRONG. While Jean has certainly been Cyclops' true love through the years and he's mourned her the countless times she's died for one reason or another, he's totally down to move on to the next love interest. In one case, he even had an affair with the villainous Emma Frost while still married to Jean.

During Grant Morrison's New X-Men run, Cyclops began having marital troubles with Jean, which led him to having a scandalous psychic affair with Emma. We guess if you're going to cheat on your wife, do it in your mind where you can't get caught? (They totally get caught.)

10 STARFIRE

Starfire Bikini

When DC rebooted its universe during the New 52 relaunch, they made many tweaks to their roster. Superman was now a bit grimmer and had a costume with a high collar. Barry Allen was now the only Flash who had ever existed. Dick Grayson had never been the Batman. And then there was the former Teen Titan Starfire, who received an over-sexualized redesign that made many readers uncomfortable and sparked a bit of a controversy.

At one point, New 52 Starfire hit up Roy Harper, aka Arsenal, for some casual sex for no other reason than to sell some comics. And to make matters worse, the other characters in her Red Hood and the Outlaws team pretty much treated her like a piece of meat as well. This was not the character's finest moment.

9 BATGIRL

Alan Moore and Brian Bolland's The Killing Joke was already a pretty controversial comic book due to the graphic rape of Barbara Gordon at the hands of the Joker, who also shot and crippled the young heroine. Well, despite the fact that Batgirl Vol. 4 #49 by Cameron Stewart, Brenden Fletcher, and Babs Tarr walked back the traumatizing events by insinuating that they might have been fake memories implanted in her brain by the Fugue, the animated adaptation of The Killing Joke went all in on the sexual violence and even gave Barbara a weird romance with Batman.

In the movie, Barbara is obsessed with Batman, who has usually been portrayed as her mentor and friend in the comics, and seduces him on a rooftop. Barbara slips off her costume and sleeps with the Dark Knight in one of the most controversial moments in DC movie history.

8 ANGEL

10 Angel and Husk

You haven't lived until you've had sex with X-Men's Angel. In Uncanny X-Men #437 by Chuck Austen and Salvador Larroca, a teenage mutant named Husk gets to experience just that. After trying to fight off his feelings for the 19-year-old Husk, who can transform into any element after ripping off her own skin, Angel finally gives in to his love for her and visits her home in Kentucky to tell her as much.

What happens next is a bit shocking and goes to show that Angel has no shame: he starts making out with Husk outside of her house in front of her mom. It gets much worse. Angel then lifts her in the air and the two begin having sex in midair while her mom and some of the other X-Men watch. Her mother turns away in embarrassment as Husk's dress falls to the ground. Hoo boy.

7 NIGHTWING

nightwing-romance

Dick Grayson is known for more than being the first Robin and his apparently attractive butt. He's also very popular with many ladies and gentlemen of the DC Universe. You've probably heard of his fling with Barbara Gordon, who has always been his true love, but he's also spent some pretty hot nights with Starfire during his time with the Teen Titans.

But his romance with Huntress (the Post-Crisis Earth 2 Helena Wayne version) tops them all. Huntress is Batman's daughter with Catwoman, which makes her Dick's sister. Well, this doesn't stop them from having the hots for each other and even spending all of their time in Wonder Woman Vol. 1 #284 by Gerry Conway and Jose Delbo debating whether they should tear into each other while their dad's away.

6 WONDER WOMAN

Things have always been pretty kinky with Wonder Woman, who was first created by William Moulton Marston, a psychologist who was interested in exploring themes of bondage and S&M through the comic. That's why the early stories always involve people tied up in "interesting" positions and gagged. Wonder Woman is also regularly spanked or flogged in the book. Don't be surprised if you see her tied up herself and even smiling in the process.

In only the third issue of the book, Diana even gets to dress her fellow Amazons in deer costumes, tie them up, and serve them on platters during a very weird roleplay holiday that you'll never see in the movies. Grant Morrison and Yanick Paquette recently explored Wonder Woman's BDSM roots in their Wonder Woman: Earth One graphic novel.

5 SUE STORM

Namor Kissing Sue Storm

Well, Sue Storm is not someone you would expect on this list, especially since she's been a married woman for pretty much her entire existence. While she's committed to Reed Richards for life -- and they even have some kids together -- that's not stopped her from participating in some flings... with Namor The Submariner of all people.

Things have always been pretty hot between Sue and Namor, who was once convinced not to destroy Manhattan with a tidal wave when Invisible Woman gave him a deep smooch. There have even been alternate realities wherein Sue and Namor were married and madly in love. Poor Reed never knew what hit him. We can assume Namor got more than a smooch in that particular event book.

4 SQUIRREL GIRL

Wolverine-Squirrel Girl

Squirrel Girl does whatever a squirrel can. This teenage hero has super strength, heightened reflexes, a tail, and buck teeth that can chew through wood. Oh, and she can talk to squirrels, of course. One thing you might not know is that she's also been known to get just a tad bit nasty. And not with the person you might expect...

In a pretty creepy development in New Avengers Vol. 2 #7 by Brian Michael Bendis and Stuart Immonen, it's revealed in a really awkward scene that Squirrel Girl once had a fling with Wolverine, who's made his way around the Marvel Universe... if you catch our drift. It's pretty disturbing since Wolverine is much much, much older than Squirrel Girl.

3 ROBIN (TIM DRAKE)

Tim Drake Cassie Teen Titans

Tim Drake, the third Robin, has saved most of the romance for Stephanie Brown (aka Spoiler), and was in a relationship with her as recently as the latest run of Detective Comics by James Tynion IV. But Tim's had some other lovers throughout his crime fighting career. There's one very notable and NASTY example that's quite a bit shocking. Remember that time Tim made out with Wonder Girl on top of the deceased Superboy's gooey remains?

In Teen Titans Vol.3 #37 by Geoff Johns and Tony S. Daniel, Tim is busy trying to find a way to make a clone of Superboy, who had recently died in Infinite Crisis, from a tank of green goop. When he fails, Tim smashes the tank and the goo gets everywhere. That's when Wonder Girl arrives to cheer up Robin with a kiss, while they roll all over the goo.

2 DOCTOR MANHATTAN

Doctor Manhattan Sex Scene Lori Watchmen

Doctor Manhattan is an all-powerful omniscient super being who is basically a god. He's exponentially more powerful and intelligent than the rest of the Watchmen cast. That doesn't stop him from giving in to his more primal instincts from his days as a human man, though. Yeah, the Doc still likes to get nasty when given the opportunity. At least until he loses all interest in humans.

But before he abandons humanity to its nuclear fate, he has a very spicy scene with his partner, Silk Spectre, who thinks she's enjoying the touch of Doctor Manhattan, only to discover that he's duplicated himself in order to work on an experiment while still pleasing her in bed. Wow, now that's something you aren't going to find in the Kama Sutra.

1 COLOSSUS

colossus threesome

Colossus had a pretty longtime relationship with Kitty Pryde back in the day, but she wasn't the first person the Russian mutant got nasty with. In fact, it might surprise you to know that Colossus actually lost his virginity in a threesome during a mission in the Savage Land! That's right, Colossus got busy with two of the natives after fighting off a dinosaur in Uncanny X-Men #114 by Chris Claremont and John Byrne.

The women were so impressed with Colossus' skills during the fight that they thought mating with him would be a great idea. That way, they would give birth to heroes as strong as Colossus. It sounds like a really bad adult film, but that's comics for you.