Loki had to fight a laugh when he saw how surprised Banner was by the honest admission of gratitude. It was nice that he could still keep these people off balance without having to resort to trickery. It wasn't that he didn't mean it, quite the opposite, but it was still good to see that he wasn't losing his touch.
He supposed that, next time he got so bored, he should try to find a trick that was a little less...dangerous to community as a whole. He could still see the humor in it, but now he at least truly realized just why others would not be in on the joke, so to speak. He hadn't imagined that it would be the man who once, in a rage, tried to break his spine, would be the one to explain it to him, but sometimes Loki enjoyed a good surprise as well.
Even though he had regarded Banner as a 'lost creature' once, he could now easily admit that he had been the same. If he was pensive enough, he might admit to still being the same. He was someone who had once willingly dropped himself into an abyss. How could he not call himself lost after such a thing? He still needed to tell Agent Coulson that he was also right about his lack of conviction, but he was holding that until the right moment. Loki always had a flair for the dramatic.
"It's amazing what a little perspective can do," he said with a slight laugh. "I'm also starting to realize that there really is a great difference in the cultures between Asgard and here. I may not have fit in at Asgard, but it seems I am still a product of the place." As much as it annoyed him.