Celebrities, of course, have their fair share of devoted fans, but some of these fans take the words "over the top" to a whole new level. And while many have had their fair share of crazy celebrity fans, some of them are just so crazy that it's almost impossible to believe.

Whether the story is crazy because the celebrity is just too nasty, whether the story is crazy because the fan is just too nuts, or whether the story is crazy because of a combination of both, these crazy celebrity fans and the stories behind them have to be seen to be believed. And, the best part about all of them is, they're all true.

So the next time you think you've heard it all when it comes to crazy celebrity fans, check out these stories and remind yourself that it could always get worse. Much, much worse.

Here's our list of the 15 crazy celebrity fan stories. Brace yourself...

Justin Bieber Is Terrible In Bed

There's a whole section of Reddit dedicated to various groupie tales, but one of the funniest crazy celebrity fan stories on this sub-board involves none other than Justin Bieber. While he was in Sweden, he linked up with a model of sorts, and she was forced to sign an NDA (non-disclosure agreement) if she wanted to hook up with him. So, she did, but she subsequently broke the NDA to tell all about her terrible experience with Da Beebz. Apparently, he's a lazy lover, and did nothing but lay there with his "average sized" equipment. Of course, since this is Justin Bieber, this wasn't the craziest part of the story -- that came when his "Beliebers" came to find out about it, and how they were signing an online petition to get her to go to jail because she broke the NDA. (But that's not how it works! That's not how any of this works, ladies!)

Adam Levine Refuses To Give Autograph Because Fan Is Ugly

Adam Levine's head must have gotten really big since he became a judge on The Voice -- so much so, in fact, that he seemed to have forgotten that prior to getting a job on this American Idol rip-off, he was little more than an ugly frontman for a mediocre band called Maroon 5. And that's the origin of this crazy celebrity fan story, though this craziness stems from Levine being a douche: one night, outside of The Voice studios, a fan asked the future Jeopardy! trivia question if he would be so kind as to give her an autograph. His response? "I don't give autographs to ugly chicks." Have you looked in the mirror lately, sir? Because you have no room to talk.

R. Kelly Is A Lot Creepier Than You Thought

We all know that the various scandals with teenage girls were the very thing that brought R'n'B singer R. Kelly down. And while many were quick to blame the girls for "getting themselves into that situation," people also seem to forget that these girls were, y'know, children. This crazy celebrity fan story comes courtesy of a former sound engineer of R. Kelly's, who claims that the singer "would have a line of super-young girls waiting to be alone with him. The girls would be all excited while waiting, and then come out kind of shell-shocked and teary, saying it wasn't like they thought it would be. I actually quit that end of the recording biz, because it made me feel so dirty." There's nothing we can say after that, now, can we?

Mandy Moore Isn't Exactly Sweet As 'Candy'

This story is a bit disappointing, as This is Us is one of our favorite shows, and Mandy Moore seems like a sweet lady. But this crazy celebrity fan story comes to us from the time that Mandy was still a teen pop star, and floundering on the charts behind the likes of Britney Spears. This story takes place in a drug store, where a customer accidentally bumped into Mandy, thus knocking over all of the things he was holding in his hands. As he bent over to pick up everything from the floor, Mandy not only didn't bother to help him, but she stood in front of him fuming for his "stupidity." He then got into a checkout line, and as luck would have it, Mandy got behind him and continued to fume, muttering under her breath about how she was "in a hurry." The man then went into a smoothie shop, and lo and behold, Mandy was behind him again, again muttering under her breath about how she was "in a hurry." But the now-former fan got even with her, and not only took his sweet time ordering what he wanted, but he proceeded to ask the cashier every inane question he could think of about the smoothie and its contents. Karma!

Rihanna's Stalker

Perhaps the worst thing about being a celebrity is the knowledge that you have stalkers. And this crazy celebrity fan story comes courtesy of Rihanna's stalker, who is nothing if not frightening. The stalker, who goes by the name Ralph Alexander on Twitter, has parked himself in front of her house in Los Angeles (even went so far as tweeting the picture to her with the caption "At Yo'House"), threatened to kill her several times, and even went so far as to send her a sexually explicit video, promising to do the same thing to her as was seen in the video! Rihanna, for her part, immediately got a restraining order against him, but it was no use, as he's been found guilty of violating it several times.

Taylor Swift Is The Nicest Celebrity Alive

Taylor Swift doesn't have a fandom -- she has a cult. And perhaps this is why these crazy celebrity fan stories about her "Swifties" only prove she's the nicest celebrity alive. As a fan tells it, "My best friend and I were at her concert. We knew from a previous concert that at some point she would perform a few songs on a small, rotating stage at the back of the venue. We made sure to be right up against the barrier. Taylor was our hero, and being that close to her made us cry tears of joy. Before Taylor went back to the main stage, she went around and hugged the people surrounding the small stage. When she got to me, she said, 'Aww, don't cry!' She then proceeded to take two bracelets off her own wrist and put them on mine. That was The Best Day."

Thanks For The Tip, Lil'Wayne

The Reddit groupie boards are filled with crazy celebrity fan stories, this one involves Lil'Wayne. As fans of the Young Money rapper undoubtedly know, Lil'Wayne has nothing but a voracious sexual appetite, and that's evidenced by the four kids that he has with four different women. And no matter how many times people refer to him as a "gremlin," the rapper certainly knows how to get women to do his bidding. And there's no better example of this than the time that Lil'Wayne picked up a woman, brought her onto the tour bus, had wild and crazy sex with her, then kicked her off the bus...but not before giving her a $100 bill to get home. Thanks, we guess?

Emma Stone Is Too Sweet For Words

There are few celebrities that are quite as nice as Emma Stone, however they may try. The star of La La Land and Ghosts of Girlfriends Past was starring in Cabaret on Broadway back in 2014, and when fans were waiting outside to greet her, the security guards told them that they were on a foolhardy venture, because it was too cold for her to come out. That's when Stone surprised them all with one crazy celebrity fan story -- according to the fan, "And you know what? She came all the way down the line, signed something for every single person, and even took pictures with all of us. It was amazing and I will always have mad respect for her."

Matthew Perry Isn't The Nicest 'Friend'

Now that Friends long off the air, you would think that Matthew Perry would realize that he's not exactly in his prime. You would think that, and you would be wrong. This crazy celebrity fan story featuring Chandler Bing (what kind of a name is this, anyway?) comes courtesy of an NBC intern: when he was commissioned to do a press tour for Studio 60 on the Sunset Strip, he refused because the places he was staying at weren't providing sugar free Red Bull drinks. When he finally did the bare minimum of press provided, he demanded that his publicist get him a car, and when it came, he refused it because he wanted something more upscale. At the end of the day, Perry abused his publicist so badly that she was in tears at the end of the day. We guess this explains why he hasn't had a hit since Friends went off the air...

Michael Jordan Doesn't Tip And You're Lucky To Serve Him

You would think that a sports legend like Michael Jordan would be humble and grateful to be where he is today, but you would be wrong. This crazy celebrity fan story comes to us courtesy of a Chicago fan: at the height of Jordan's career, when he was the darling of the Bulls, he used to like to play golf in his limited free time. On this day, Jordan went golfing with a bunch of his buddies, and when the day was over, all of them had tipped their caddies except for the legend himself. The caddy, fearing that he didn't do a good job, asked Jordan if he'd done a good job, because he was about to leave. Jordan snarled and shouted, "What, and you want a tip? You should be grateful to be carrying my clubs." Geez!

Morgan Freeman Did The Most Morgan Freeman Thing Ever In The BVI

Celebrities need a vacation too, and Morgan Freeman is no different. This crazy celebrity fan story comes to us from the British Virgin Islands, where the fan and her husband were in an otherwise abandoned restaurant. The only other patron in the restaurant besides the fan and her husband was the aforementioned Morgan Freeman. After the couple confirmed it was, indeed, the Through the Wormhole host, Freeman came over to talk to them, and the three spent the rest of the afternoon together, chatting and getting to know one another. The woman said that Freeman was "calm and wise, as you'd expect him to be."

Bill Nye The Science Guy Played Matchmaker, Inadvertently

Bill Nye The Science Guy has been teaching children of all ages about science since, seemingly, the beginning of time, and he's earned a loyal following as a result. And this crazy celebrity fan story has a bit of a sweet ending for the fans involved: after he gave a lecture at an undisclosed college, two people who didn't know one another went up to the stage to take a picture with him. When they got up there, Nye encouraged them to both get in the picture with him. (Later, Nye would say that he thought they knew each other, but was wrong.) But it all turned out okay in the end, because the two ended up talking after the photo was taken, and five years later, they got married. She blinded me with science, indeed!

Ryan Seacrest: Diva!

This is, perhaps, one of the funniest "rude celebrity" stories that we've ever encountered. This crazy celebrity fan story about former (and possibly current) American Idol host Ryan Seacrest happened at the height of the AI craze: Ryan Seacrest was on his way to board a private jet to wherever it is he went when he realized that there was no ice. He then grabbed an operations manager and angrily shook him while demanding ice. The operations manager told him that not only wasn't this his job, but he was escorting another private jet off the runway, and Seacrest responded by snapping off and demanding to speak to a manager. When the manager arrived, he told Seacrest to get lost. Seacrest...out!

Hugh Laurie Proves He's Nicer Than His House Character

Hugh Laurie has made a bit of a career playing a curmudgeonly doctor on the hit drama show, House, but in this crazy celebrity fan story, he proved that he's much nicer than his counterpart ever could be. At a grocery store in New York, a woman was asked to pay $13 for her groceries, but when she went to pay, she'd realized she forgot her credit card in the car. Before she could go out to get it, Hugh Laurie volunteered his credit card and paid for her food. Even though the woman insisted that she didn't need it, he insisted that he should pay. After the woman thanked him, Laurie told her, "Now promise me you'll go and do something kind for someone else, OK? I have a feeling you will." That's awesome!

The New Kids On The Block And Their Voracious Sexual Appetites

Much ado has been made, over the years, about what "whores" the New Kids on the Block are, and fans offer no better proof of their slutty ways than their annual cruise, wherein all types of bodily fluids are exchanged between the not-so-new and not-so-kids-anymore and their fans. But one of the crazy celebrity fan stories that we found absolutely hilarious involved New Kids' heart-throb Jordan Knight. While he was on his solo tour, he made a stop in New York City and propositioned one of the women who worked in the venue where he was playing. The woman, being spoken for at the time, declined the offer. The next night, Jordan was in Boston performing, and again, he propositioned one of the women who worked in the venue. This woman, unlike the New York woman, accepted his offer. However, the Boston woman later reported that Jordan "kept trying to flip [her] over" during sex, preferring, apparently, to "enter through the back door" in the bedroom. ALRIGHTY THEN!