This was about to suck, and Stephen knew full well Zee's head was about to explode. A lot of things just got dumped on her and now this. This was not how he'd planned to tell her he loved her. Well, he didn't exactly know how he'd planned to tell her, but this wasn't it.
Then Arabella disappeared before he could stop her, leaving the two of them alone to talk about this. Oh this was about to be amusing.