"So... Why did I hate you, again?"
Jason squinted, trying to search the depths of his fragmented memory for an answer. He'd had an accident while on patrol, and while unlike a certain older brother of his Jason hadn't taken on a whole other persona because of his amnesia, he still couldn't remember much from his life before waking up at the hospital. Some people, like Bruce, he still remembered to an extent. But most people were just strangers to him now, and this supposed nemesis of his was no different.
His so-called enemy had showed up at his door wanting to rebuild their contentious relationship, for some reason beyond his comprehension. But he didn't hate this person, not anymore, and he was struggling to find a reason to. The surprise visitor had been nothing but polite, respectful of Jason's memory loss, and despite the conversation being understandably awkward, it'd been...pleasant?
Also, the more they talked, the more Jason found himself drawn to this "archenemy" of his. For the most part he only had lingering impressions of people he'd been close to before his accident. Like, he felt a familial bond with his siblings, with Bruce, with Alfred. And he was still vaguely attracted to his exes. And he felt a profound hatred for people like the Joker. Those made sense.
This? The butterflies in his stomach? The fact he couldn't stop thinking about how cute that awkward smile was? The way his heart did a flip at those eyes? This made no sense! They'd supposedly hated each other. His former enemy wanted to be enemies again. So why the hell was he crushing like a schoolboy?
"Look, I dunno. I don't hate you? You seem fine. I mean, I guess we could punch each other a bit? See if that sparks a memory?" Punching wasn't exactly what he had in mind right now, but you know what? He'd take it. The truth would be too awkward. "I'd tell you to insult me, but it's hard to be offensive to a guy who can't remember jack, so..."