Honestly, I see a lot of writers lean way too hard on the 'brothers who finally reconcile' trope without putting in the groundwork. It can feel rushed, you know? The good fics I've saved dig into the centuries of messed-up history 'Seven Deadly Sins' glosses over. One author had Meliodas and Zeldris just... sitting in silence in the Demon Realm for chapters, remembering small things—how their father praised one and ignored the other, the sound of a certain training ground. The bond wasn't built on big battles or dramatic apologies, but on them slowly realizing they'd both been alone in different prisons. The emotional payoff hit harder because the connection felt earned, not declared.
Another angle I appreciate is when writers use external threats to force cooperation, but not in a cheesy way. Like, a story where the 'curse' on Meliodas has some weird backlash affecting Zeldris, tying their fates literally. They're stuck together, forced to navigate a shared vulnerability, which peels back layers of defensiveness. You get these grudging moments of care, like Meliodas casually blocking an attack meant for Zeldris without even commenting on it. Those silent actions speak louder than any 'I love you, brother' monologue ever could.