The road ahead of them wouldn't be smooth sailing and if Iris chose to be by his side, he didn't want to tone down his actions on her behalf. This was something that he would do underhandedly, this was something that he couldn't avoid when he made a plot and schemed against the royal family.
Just like what Haco had said; one would eventually become a monster when they hunted down one.
This was only one example, but ahead of them, there would be more like this that would happen, countless moments where you would be demanded to shed all of your morals and focus on what you wanted to achieve.
And after knowing that, would Iris still choose to stay by his side?
Once again, Cane left the choice to her.
Iris had said she wanted to stand by him and help him, but this was the kind of help that Cane needed and he was not sure she could handle it.