I didn't think I'd be into it, honestly. The premise always sounded ridiculous on paper. Then I stumbled across this one on AO3 called 'The Gravity of Crimson'—it's a complete AU where they're neighbors in a crumbling apartment building. The author nails the push-pull dynamic not through violence, but through shared, crushing loneliness. Bruce brings him groceries when he's sick; Joker leaves absurd, cryptic notes under his door. It's less about romance and more about two broken people recognizing the same emptiness in each other. The prose is sparse but heavy, and it left me staring at the ceiling for a solid hour after finishing. Changed my whole perspective on the ship.
If you're willing to wade through tags, the 'Bats and Jokes' collection on some older archives has some brutal, cathartic pieces from the early 2000s. The emotional core there is often rage and a twisted form of understanding, written with a raw intensity that newer, more polished fics sometimes sand off.
Archive of Our Own is basically the main hub now. The tagging system makes finding the dynamic you want a lot easier—you can filter for 'The Joker/Bruce Wayne', 'Batman/Joker', or the broader 'Batman - All Media Types' fandom. The sheer volume there is kind of staggering; it’s where the really long, plot-heavy explorations tend to live. I see a lot of the psychological deep dives and darker AUs posted there.
That said, I still browse FanFiction.Net out of habit. The interface feels old, but there's a ton of classic stuff from the 2000s and early 2010s archived there. The vibe is different—more of the foundational 'enemies to whatever this is' stories that shaped a lot of the current tropes. It’s worth poking around for that historical perspective, even if newer authors mostly migrate to AO3.
Sometimes the best, most unhinged snippets pop up on Tumblr or Twitter, though. You have to follow the right tags and be ready for a lot of fragmented threads and headcanons, but the immediacy of the reactions there is a whole other experience.
Yeah, exploring that relationship in fanfic isn't really about romance for most writers, at least not in a traditional sense. It's a pressure cooker for psychological power dynamics. The stories often frame Joker as the only one who truly 'sees' Batman, who strips away the Bruce Wayne persona and confronts the obsessed, vengeful man underneath the cowl. It's a horrific intimacy built on mutual obsession.
I've read stuff that positions Batman as the ultimate straight man to Joker's chaos, where his rigid code is the only thing holding back total anarchy, and Joker's whole existence is a performance to crack that code. The conflict becomes a perverted dance—Joker needs Batman to give his crimes meaning, and Batman, by refusing to kill him, validates that need. It's sick, but that's the point. The best fics make you squirm because they understand the dependency.