Ivy listened to The Joker's monologue, for that was surely what it was, sitting up straight and not allowing herself to be frightened for one possible second, which had to be drawing even more attention to them. She had nothing to be afraid of from him, his poisons couldn't hurt her, and here in Arkham surely she could get away fast enough, throw a pesky human or two in the way as she escaped anything he might try, but he was intimidating and she would be lying if she said otherwise, even she didn't dare to release her pheremones on Joker to subdue him, who knows how he would react to them? It wasn't often two of Gotham's costumed criminals put on a show for everyone to see in Arkham's communal area.
Ivy tried not to visualize his words, but it was too strong of an image to resist, and things similar to what he was describing had happened before and the memories were so completely tramatizing. She had an entire rain forest that she had been years growing burned completely down, she had put too much of herself into plants in the beginning, killing them by accident with her toxins. "There is definite truth to your words. Things like that have happened to me before and so here I am."