Ianto still didn't like the idea of talking to Jack through Jessica. Not when he already knew he could speak with Jack alone, in private. But it was clear that Jessica wasn't going to go away any more than Ianto was.
"As if sharing him with you has been fun for me." Ianto sighed. "I know it isn't reasonable to ask you to never speak to Jack again, but I don't feel reasonable." Which makes sense, considering what Jo had said about ghosts deriving their power from emotion, and memory. "I don't know what's going to be the best solution for us. And to be honest, I'm terrified that it will all end very badly, either way."