Harley Quinn, real name Dr. Harleen Quinzel. about early 20's or mid 20's, was once a young intern at Arkham Asylum, there she meets the joker , there she become his psychoanalyst
then he told her a bit of his past. he came from a broken home his mom ran away when he was 5, his dad was mean to him & never saw his dad be happy or laugh , once his dad took him to a circus when it got to the clowns they made his dad laugh, later next day joker did the same thing like the one clown did, but his dad gave him a black eye , after alot of talks little by little she started to fall for him later joker escape Arkham & killed a lot of people, Harleen worryed like mother hen was about to look for him when batman came in draging the clown in the Arkham halls, a bruised & bleeding joker,Harleen snapped. How dare that pointy-eared creep treat her poor puddin that way ? Doctor-patient relationship be damned; her puddin was more important than any job, anywho. Harleen rushed home to find weapons and equipment and stole a harlequin outfit from a local costume shop. After all, to save her puddin, one must look the part. She busted into Arkham,took the Joker out with her, & now called herself Harley Quinn. since then she has been joker's moll, She has been in and out of the Asylum, both as an escapee and as a rehabilitated patient, over and over again.
Her infatuated love for The Joker dominates her life; he is her motivation to the life of crime which she leads in order to remain close to him. Almost all of her actions are done with his happiness in mind. She is terrified of him and insanely in love with him and can barely imagine a life without him. Her sick infatuation leads her to carry out his every beck and call and she is cowed by him and utterly adoring of him.
Their relationship is a complex one, following a similar pattern to the typical abusive relationship. Joker physically and psychologically assaults her, then draws her back in with comfort and affection. She makes the vow to walk away, only to find he is a drug she cannot be rid of. Her attempts to stand up for herself are eventually dismantled by either his threats, or her fear of losing him. With someone as insane as The Joker, his reason for keeping Harley around instead of killing her are uncertain. Almost definitely, he views her as a 'toy' - something he created, and most likely he values this; his ability to reduce an independent, attractive and successful young woman to a willing slave who has given up all hope of a normal life for him. Doubtless her undying adoration holds amusement for him; and is a reflection to him of his own ego.
But it is also very possible that Harley truly has touched Joker in some way. The Joker is renowned amongst all as being one of the most dangerous and unpredictable maniacs the world has ever seen, generally accepted as loving no one but himself - as not even seeing other people as 'real', but merely as objects to play with. Yet it seems that somehow, Harley has penetrated through the twisted paths of insanity to touch some long-forgotten core deep within him.
For her part, Harley will never truly be free of her love for Joker. She is utterly infatuated and will remain so, even during her periods of 'sanity'. He has completely bent her mind to his and changed her life for ever.

Most of the time she's pretty happy about it. Harley has a vivacious, effusive and highly expressive personality, quick to show affection for her loved ones, just as quick to anger and snap. She is a woman of extremes in all things. Her mood swings, whilst nowhere near as violent as Joker's, are still mercurial to the extreme. She experiences all emotions intensely and passionately.
She is undyingly loyal to her two best loved ones - Joker and Poison Ivy - and often ends up as a bit of a 'door mat' to both of them, being cowed by their more dominant personalities.
Whilst Harley seems merely zanily playful, she is absolutely insane, unpredictable and therefore highly dangerous. Her love for The Joker makes her fiercely defensive and protective of him and she will go nuts in order to do so, or to defend their love to anyone who questions it. She will do whatever it takes to help his dreams come to fruition - as mentioned above, she's a highly determined and fixated woman - as well as pursue her own goals with the same fervour. Harley believes that The Batman is the source of Joker's pain and hates him as a consequence. This makes her a deadly enemy to the Dark Knight, none more so than when she is fighting by the side of her man. when she & joker have a sour patch she can all ways come to Poison Ivy (or red as for her hair) the two become pals. when Joker, frustrated with Quinn, kicks her out of the gang, so she steals the Harlequin Diamond(they were planing to steal it but batman stop them) in a museum to prove her worth. At the same time,Poison Ivy robs the museum of plant toxins. The two become quick friends and Ivy takes her back to her lair in a toxic waste dump where she takes care of her and injects her with a serum which has given Harley an immunity to all toxins and poisons. Harley and Ivy team up for a number of successful capers, becoming Gotham City's "Queens of Crime". anyway back at joker's place he wonders where are his socks & place a mess & bud & lou snap at him & ask his two muscle men Rocco & Henshaw were Harley is? they told him that he kicked her out , joker told them that she all ways comes back , rocco told him not this time boss did you not see the papers, & joker said what papers & looked at that days paper that said "Queens of Crime" when he saw it he scaremed so loud that it knocked the sighed outside, anywho as batman he knew were two "Queens of Crime" were at , but had to ware a gas mask, so in end batman got the three & ivy was little mad at Harley but made up in the end same as joker.

But Harley & ivy can still be pain in cape for batman when they team up. harley once helped batman & robin (dick grayson) to look for joker becase he stole a black market atomic bomb so batman & harley team up to look for him in some new hideouts, asks if she can get changed & he ok it when she is changing he looked a round found that the Mayor's & D.A.'s & Gordon's office are bugged with hidden camera's, he was about to ask harley when bud & lou attack him it was a good thing harley showed up becase they were going to eat him, she had two big steaks for them just in time to save batman, after looked the at hideout 1 they looked at hideout number 2 a big old bilding harley was going to use her grappling hook that looked joker but it hit her head so batman used his & talled harley to hang on & up they go to a open window ! harley had to cacth her breath batman looked a round found find this hdeout is a mob gambling party, run by "Boxy" Bennett, where batman is captured. As robin sneaks in to help Batman, while Harley sings a dark but funny song called say that were sweetherats again to distract the gun-toting party goers.
After they escape, Batman gets impatient and demands to know where Joker is. Harley laughs and mocks him for not having figured it out already: Joker is holding Mayor Hill prisoner at his mansion, using Hill to distract the cops. when they got there now that Harley's end deal is done batman handcuffing Harley in the batmobile, over her protests, Batman and Robin sneak onto the mansion's grounds, finding the bomb on the lawn and Joker frolicking in Hill's swimming pool. Hill asks that Joker just make his ransom demand, the city will gladly pay it. Joker says he's not planning to ransom the city — instead, he's just going to explode the bomb and take care of the cops and Batman in one fell swoop. He and his goons already have an old-fashioned biplane set up on the grounds to escape the explosion.
Batman and Robin appear, and fighting ensues. Harley, escaping her cuffs, appears and pins the two up. "Deal's off, B-Man. Nobody said anything about hurting my puddin & said & here you thought I was just another blonde-headed bimbo! Well, the joke's on you: I'm not even a real blonde."
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Joker is somewhat surprised to see Harley there, but cheerfully invites her to board the plane with him. He starts the bomb's timer: 10 minutes.
Robin points out that Joker didn't leave enough time to swing by Arkham and save Harley. Joker laughs this off, but Harley also realizes that there isn't enough time to save their fellow inmates like ivy or her other pals. Since the clock is ticking, Joker tries to override her objections, but she panics when Batman mentions their pets. "I'll buy you a goldfish!" Joker yells, exasperated, "let's go!" Harley resists, and he flies off without her.
Harley frees Batman and Robin free just as Joker circles around, strafing the ground with the plane's machine gun and dropping bombs. Batman manages to evade them, and Robin successfully defuses the bomb. Now totally crazy, Joker sends his plane on a suicide dive toward the bomb, firing the machine gun at it, saying it's going off, one way or another. But Harley fires a pinpoint shot with a spring-loaded Joker head, hitting Joker and knocking him into a daze. He loses control of the gun and shoots his own fuselage, and the plane crashes into the Mayor's mansion.
As Joker stumbles out of the wreckage, Harley levels the machine gun at him. Batman yells for her to stop, but they are too far away to prevent her. Joker scoffs, saying she doesn't have the guts to shoot him.
She pulls the trigger, Joker flinches — and a flag that reads "RAT TAT TAT" pops out of the barrel. Batman and Robin sigh in relief. For a moment, Harley looks afraid of Joker's reaction, then he laughs and says, "Baby, you're the greatest!" They embrace each other, their nonsensical romance rekindled.

harley can still be pain for batman without joker or ivy , when harley once got a parole & this how the story goes, At Arkham Asylum, Harley Quinn is jubilant to receive a clean bill of mental health from her doctor, and be granted parole. Batman and Robin, in the process of returning Scarecrow to Arkham yet again, offer their congratulations, but warn her to stay out of trouble. She declares that, starting the next day, she'll show the world just how sane she is.
The next day, she is ambling down the street on roller skates, looking for all the world like a car-hop on her day off – except she's taking her two rabid pet hyenas for a walk, and passerbys are scrambling to get out of her way. Thinking the problem is her outfit, Harley ducks into a department store.
Inside, Bruce Wayne is reluctantly trying on clothes, with the help of Veronica Vreeland. Harley catches sight of them and cheerfully remembers when they last met – during a hold-up by the Joker. Picking out a new dress for herself, Harley buys it at the register, but rushes out before the clerk can remove the security tag. The clerk calls to the guard at the door, and he asks her to stop.
Harley panics, thinking she's being arrested again, and knocks over the security guard. She rushes into the dressing room, and comes out again in her clown costume. Running outside with her hyenas, she jumps behind the wheel of Bruce's car, with Veronica in the backseat, and roars away. As she does so, Harvey Bullock swerves his car to avoid her and crashes into a hydrant. ("Oh, you're gonna pay for that!") Bruce is left standing outside the store.
Hearing his daughter has been kidnapped, General Vreeland angrily confronts Commissioner Gordon, who reassures him that Harley is confused and scared, and doesn't intend to hurt Veronica. General Vreeland refuses to accept this, and calls for military backup.
Batman and Robin team up and Batman deduces that Harley will go to someone who can hide her and then sneak her out of town. Sure enough, she has gone running back to Boxy Bennett, who hasn't forgotten their last meeting. However, he's still a sucker for a pretty face, and eager to exchange Veronica for a fat ransom. Harley objects to this, saying Veronica is just a bystander, and will go free as soon as Harley is away. Boxy begins to argue, and just then Batman and Robin arrive and tackle Boxy's thugs. Harley grabs Veronica again, and jumps back into the car. Boxy narrowly escapes a mauling by Harley's hyenas, and takes off after her in a truck. As they speed along the highway, Veronica asks if Harley was sincere about letting her go. Harley says yes, she's finished with crime, only she has to get out of town since no one will believe that she didn't mean to kidnap her. Veronica offers to not press charges, and also to speak up for her with the police, if Harley stops. Harley is overjoyed, thinking her day is finally turning around – then a cannon blast narrowly misses the car, and the two women look to see General Vreeland riding a U.S. Army tank down the road at them. Harley speeds away again, then halts in the middle of an intersection in the theatre district, with Bullock, Boxy, and Vreeland bearing down on her from three directions.
There is a humongous crash, and the Batmobile arrives a second later. As the drivers get out to look at the wreckage, Harley calls from a rope above, drops Veronica into Robin's arms, then takes off. As Batman takes off after her, General Vreeland hugs his daughter, while Bullock contents himself with arresting Boxy.
Up on the roof, Batman urges Harley not to throw away her hard work and her freedom. Harley attacks, ranting about the string of troubles she's had. As Batman avoids her kicks, her wild moves take her to the edge of the building, and she ends up hanging for dear life on a collapsing billboard. As it gives way, she falls, but Batman saves her. He sets her down, all the fight (and, it seems, the contents of her stomach) gone out of her.
Batman and Robin return her to Arkham, but Dr. Leland assures her it won't be for long: Veronica, true to her word, dropped the kidnapping charges and it should only take a little more work before Harley's ready to interact with "normal" people again.
Harley asks Batman why he has been looking after her when she's been nothing but trouble to him. He says he can only sympathize with her honest desire to lead a normal life: "I had a bad day too, once." As a parting gift, he gives her the dress she bought. Ecstatic, she plants a big kiss on his face, before returning to her cell.

Harley is still in love with joker & still pals with ivy & a pain to batman & his pals, & superman ! but that is a other bio.

Harley loves joker likes some of schemes all but one, The Laughing Fish scheme she hated fish they make her sick , when Bullock found the hideout he was captive joker was planing to feed him to a shark when he realizes that Batman will arrive soon and he's the one Joker really wants. he said If this lunch meat figured out where we are, Batman won't be far behind. And why spoil my sharky's digestion, when I can feed him bigger fish? Harley said Eee-yuck! Again with the fish! I HATE fish! (notices Joker's glare) Uh, no offense, Mr. J. Joker: Poor Harley. This whole caper's been really touch on you, hasn't it? Harley: Uh-huh, Cheer up! You can be my own little mermaid! (Harley gives a little squeal of delight... then Joker jams a giant rubber fish head over her, and laughs.) Harley: You're really sick, you know that, boss?
Joker: Mm-hmm. later he talls batman, You're right, Harley. Fish are disgusting. I think I'll start using my toxin on cattle. Joker Burgers! Ha! Talk about a happy meal! in the end joker was to beleave to be eaten by the shark & Harley to Arkham.