Everybody jumps straight to Harley, but Ivy’s dynamic with Bruce is this weird, slow-burn ecological horror story waiting to be written. The man is a creature of the city, of stone and steel, and she wants to tear it all down to make room for green. I stumbled on a piece called 'Photosynthesis' a while back that nailed it—Bruce trying to 'rehabilitate' her by funding a massive botanical conservatory, and Ivy just using it as a base to engineer hyper-aggressive kudzu. The tension wasn’t romantic so much as a philosophical war, with Gotham as the battleground. They never even kissed, but the way he’d visit her cell just to argue about humanity’s place in nature felt more intimate than most smut.
It’s a pairing that works precisely because they can’t change each other. She sees his mission as a futile pruning of symptoms, and he sees hers as genocide with a pretty leaf wrapper. That fundamental, irreconcilable conflict is where the good stuff lives, far from any simple 'enemies to lovers' trope.