I wish I was as composed as you. You’re still calmly explaining things to that dumb fuck, while they move the goalposts back and forth:

• first they lie I was saying there were no victims;
• then they backpedal and say “It doesn’t matter if there’s a victim or not. It’s the depiction of CSA that is illegal.”;
• then they backpedal again and say what boils down to “talking about morals bad! Also I’ll talk about MY morals. I don’t see moral difference when people are harmed and when they’re not” (inb4 I’m abridging it)

All of that while they’re still pretending to argue the same point. It reminds me a video from the Alt-Right Playbook, called “never play defence”: make dumb claim, waste someone else’s time expecting them to rebuke that dumb claim, make another dumb claim, waste their time again, so goes on.