I've spent way too much time reading 'Jujutsu Kaisen' stuff online, and the Gojo and Geto dynamic is a massive draw for writers. It's fascinating because canon gives you this perfect tragic arc – inseparable at school, then that ideological split, ending with Geto's descent. Fanfiction often digs into the 'what if' of it all, the moments we didn't see. Was there a specific conversation that could have changed things? A lot of stories focus on their youth at Jujutsu High, fleshing out the camaraderie, the stupid jokes, the unshakeable belief they'd change the world together. That foundation makes the later fracture hurt more.
Some fics explore Geto's perspective during his fall, trying to rationalize his genocide of non-sorcerers, and whether Gojo ever truly understood that loneliness. Others do post-Shibuya or even post-canon AUs where Geto is somehow revived or never left, forcing them to confront the wreckage. The tension isn't just romantic or platonic; it's philosophical. Their friendship was the core of their identities, and seeing it weaponized against each other is where the best angst comes from. I lean toward stories that don't shy away from the moral ugliness, the genuine betrayal, rather than smoothing it over for a neat happy ending. The complexity is the point.
A niche I enjoy are 'missing scene' fics set during the Star Religious Group incident, that year Geto was building his cult. What was Gojo doing? How much did he know? Those gaps are a playground for exploring grief, denial, and the failure of even the strongest to save the person who mattered most.