Man, where do I even start with this one? There's a whole universe of 'what ifs' swirling around Yuji and Sukuna, and most fics latch onto that forced intimacy of sharing a body. You get a lot of internal monologue stuff, obviously, because how else do you explore a dynamic where they're literally stuck with each other? The classic is the 'enemies to reluctant allies to maybe something more' pipeline, but I've seen it done with so many different flavors. Some writers go full horror with it, emphasizing the body horror and the violation, making it super dark and psychological.
Then there's the opposite end—the fics that lean hard into the potential for mutual understanding, the 'only you can understand my pain' angle. They'll dig into Sukuna's ancient loneliness and Yuji's survivor's guilt, twisting it into a bizarre form of codependency. It's less about romance sometimes and more about exploring a profoundly messed-up symbiosis. I've even stumbled into a few AUs where Sukuna gets his own body early on, and it becomes a straight-up predator/prey or captor/captive scenario, which has its own set of problematic-but-compelling tropes attached.
Honestly, the most interesting ones to me are where the power dynamic constantly shifts. One minute Sukuna's in control, mocking Yuji's weakness, and the next Yuji does something unexpectedly stubborn that throws a wrench in Sukuna's millennia of experience. That push-and-pull, the constant battle for dominance both physically and emotionally, seems to be the core engine for most stories in this tag. It's rarely fluffy, you know? Even the softer moments come with a sharp edge, a reminder of the inherent toxicity. I keep coming back for that specific brand of narrative tension, even when the logic gets a bit wobbly.