They work perfectly

Batman tried to hold his breath to avoid inhaling the spores, but eventually he had to breathe them in. He quickly felt his mind slow down and become duller, as if he was drunk, and he was becoming very aroused.

Ivy saw Batman's typically stern face soften as he looked at her with a big dopey grin and he said "Wow Ivy, you're so hot. I don't know why I haven't fucked you yet."

Ivy chuckled as she said "Don't worry Batman, there'll be plenty of time for that soon enough, but for now," she gestured and a flower sprouted from the ground "just open wide and breathe this in."

The flower sealed itself around Batman's mouth as a transparent pink cocoon grew from the ground and enveloped him. The cocoon filled with liquid as Batman closed his eyes. Ivy smiled. The flower was pumping him full of concentrated pheromones, except these weren't like her regular pheromones. Firstly, these new pheromones didn't wear off. They would attach to the cells and cause them to reproduce more pheromones naturally, so that there would always be a constant supply. Secondly, these new pheromones would make Batman be completely and deeply in love with her. His world would revolve around Ivy. He would be submissive to her, but he wouldn't be a mindless drone and he would challenge her where appropriate. He would obviously do anything for her and see her as the sexiest woman alive - if he didn't already. The liquid in the cocoon would rejuvenate his body and make him stronger than ever - after all, Ivy needed him to be in top form to take on anyone who stood in their way.

As she watched him in the cocoon, she smirked and thought to herself, Batman is finally mine.