Their first time, it had just been the fight. Batman had hit him, he'd hit back, and so they had continued for a while. But by the time the Bat finally had him pinned to the floor, the Joker had taken so many hits he couldn't resist the pleasure that was taking over his mind. So he had started touching himself.

At first, Batman had simply stared, but then, he'd come closer, and then the Joker was so far off in pleasure he couldn't possibly have defended himself even if he'd wanted to.

But Bats hadn't hurt him, not much anyway. He'd simply fucked him. And even while the sex was mind shattering good, Bats had fled out the window almost the moment he came, leaving the Joker in a mess of the usual blood and the new aspect of sticky sperm.

Next time they met would have been awkward, if the giant Bat hadn't thrown himself over the Joker and done the same thing to him again. And then, after going out the window and being gone for half an hour, come back to do it again.

Soon, they began trusting each other in those moments post-bliss, and Batman started spending more than five seconds flat on the crime scenes. They both took their time to get ready (and able) to leave before actually doing so, extending their time together by a couple of minutes of silence and utter peace, something the Joker had never experienced before. He liked it, and once he had figured it all out he tried to make Bats stay behind for longer periods of time by all sorts of tricks and games.

When Batman finally put him against the wall about it, he admitted it flat out. That was also brand new to the Joker.

But Bats only laughed at him, and told him all he'd have to do was ask. And there was no telling who was more surprised at it.

After that, Batman took to hanging around after their combats. He still wouldn't come unless there was a crime to stop, but when he did, he stayed. And more often than not, they had sex more than once. A few times, they spent whole nights fucking away like bunnies in run down apartments or wherever Joker had his hiding that particular time before Batman had him shipped off to Arkham Asylum again. The Joker never once told about them.

But despite the dramatics and capes, they were only men beneath it all, and thus they had to rest between rounds. It was in these minutes of total calm they started talking in controlled voices and words about the way they viewed the world. For the first time ever, the Joker told the actual tale of how he came to be. At least as much as he remembered from it. And oddly, Batman seemed to understand.

That was when Batman started to show up before the Joker got something big in motion, and slowly the Joker realized his big plans weren't as much fun when he could skip right to the Grand Final with the Bat instead of preparing and prying with people.

He still killed, of course. Don't get the wrong ideas, just because the big hero fucked him didn't mean he'd caught the Saint Virus or anything. It just wasn't as important to make it big anymore, just wasn't important to show the whole world. It was more like a hobby than a full time job, by then. When he got the pay checks every week anyway, there was no point in doing the actual work anymore.

There must have been trust between them back then, after only having been intimate with each other for a month. Something instinctively knew that they were the same, and therefore should look out for one another's best. If no such feeling had existed, neither of them would have been willing to trust the other with their bodies. The depth of it was best, if not only, described when Batman trusted the Joker enough to let him take his dick in his mouth the first time around. Since trust was also something brand new to the Joker, he hadn't quit understood it at the point, but since he wouldn't gain anything from biting down he didn't.

It wouldn't be worth the laugh.

Joker had been first to strip completely, simply because being naked didn't bother him much. He could handle his own well enough anyway. But none the less, he saw Bats as an equal, and wanted it to stay that way. So he started doing his best to undress the other man too. As silly as it may have seemed at the moment, Joker discovered something that could easily be turned into something he could use against the Bat. After it all, when Bats was pulling out, he was surprised to find his body completely bare. But the Joker decided to not use that knowledge in any way.

That was when he realized he had fallen in love with that overgrown, flying piece of rodent.

And that was when his independency became threatened, by no one but himself, and he decided to bring as much wreck to Gotham as he possibly could, to distract himself and try to forget it all. This eventually led to him killing the pretty Rachel Dawes, and thus almost accidentally uncovering Batmans true identity as the spoiled playboy brat Bruce Wayne. But he didn't use that against him, either.

And to thank him, Bats sent him back to Arkham Asylum.

Sure, it was nice with a bit of a vacation, and he was out on the loose again soon enough, but in the meantime, while he stayed there, all he could ever think of was Batman, so close to snapping and killing him, so close to off him for killing the mother of his future children. But he hadn't.

And once he was back on the streets, well, that was when things started getting really interesting.

The Joker had lost hope of the Bat ever coming back after a while in freedom with no visits, and he thought that he had crossed some invisible line or other that he didn't understand. He started planning on general chaos again, worse than ever before, just to fill the hole Batman had left in him with something, anything at all. He was at that point willing to try anything to feel something but the emptiness inside him.

It was during one of those nights, when the only thing that ever broke the suffering was overtaking darkness, that the Bat finally came out of his hiding, and did he ever know how to make a ground-shaking, heart-breakingly amazing comeback.

It was hard and sweaty and full of the battle for dominance as always, but this time, there was a definite difference. Joker couldn't tell if it was in the brutal kisses, the playful biting, or the never-ending tease of licking and stroking and flexing and bending, but something was slightly off. There was so much more feeling, so much more depth to it all.

So much more trust.

And this time around, neither of them noticed what it was that had changed when it was over. Not when they begun a new round either, not even when the Bat whispered how much he'd missed the other and Joker buried his hands in soft, dark hair.

Neither of them noticed as Joker for the hundredth time told Batman 'You complete me', not when Bats for the first time said it back, or when the warm feeling it inspired in the Joker made him come harder than ever before.

Then morning finally came and they both craved sleep; it was time to put the clothes back on. Still, neither Joker nor Bats noticed anything was wrong. Not until there was only one, small, black thing left on the floor.

The Bat mask.

Joker looked up instinctively, and despite the fact that he'd been staring at the man all night, he for the first time saw the face that was usually so well hidden behind black leather.

Batman started to panic when he noticed, sweeping the mask up and putting it on as if hoping the Joker hadn't noticed anything, rushing out and away.

"I won't tell, you know," Joker said, just as the Bat was going out the window again. He stopped on the windowsill and turned around.

As he looked at the Joker, something dark crept into his eyes and his mouth twisted in an ironic smile.

"Don't worry about it. Maybe they'll even let us share a cell in Arkham."

And when Bats fled out the window and Joker was left imagining what it'd be like to have the other man all the time every day, and the faces of the watchmen as they were discovered, that was the exact moment the Joker realized Batman loved him too.