It was all a bit much, but if there was one thing Oswald was good at it was listening. Two things? Listening, and taking note. What Harley was saying to him was all at once perplexing, surprising, and...given that they were talking about a Gotham in another dimension, or another time, or another something, somewhat sensical. There were enough similarities in her story of the city to his own that he assumed he could take her words at face value. There was no benefit to her lying to him, especially if - as she said - he had been around longer than she had from where she was standing. Some things, some very important things, were different. Keeping penguins seemed over-the-top even for him, but he was fond of purple - had even taken to dying bits of his hair deep shades of the color lately.
That Mister J she spoke of sounded like quite a piece of work. Actually...he sounded a bit like either of the Valeska twins on steroids, and he wondered about a possible link, but given the history she described between them he thought it best not to bring it up. At the mention of Batman he had snorted, but as she went on it seemed he was much more of a risk than the name implied. At least if he was due to exist in the Gotham this Oswald knew, he hadn't risen to any sort of fame yet.
By the time Bruce came skidding into view in front of them again, panting and laughing (Oswald scooted a bit further away) his head was so full of things to think about he could hardly be bothered by the presence of such a creature. There was a pause, and Oswald swallowed. One thing in particular was sticking out to him, and it was highlighted as truth by the fact that Harley had come ripping across town at the drop of a hat just because he had shown up.
"So you and I," a pointed finger wagged once, quickly, between their bodies, "we're...friends?" There was no disdain in his voice when he asked, he just wasn't used to that particular idea. Still. Even after so many years of building and rebuilding an empire. There were so few people he could rely on, and he couldn't imagine a universe where Harley would top a list like that. But maybe.