It was a strange feeling, not belonging in the universe one resided in. It was as if his mind, realizing that it had been misplaced somehow, now refused to interact with anything around it for fear of harm. He supposed the best way to describe it would be as a sort of emotional numbness, a detachment from what was (now) reality.
This often proved to be quite inconvenient.
Forgetting to eat was actually one of the more manageable effects. Seeing as Rosalind took her meals like clockwork, it wasn't hard to match his schedule with hers - unless they were apart, which was increasingly infrequent. Even then, the timepieces strewn about the city, combined with simple habit, kept him from being truly malnourished.
No, the most irritating issues with this condition were far less noticeable to those unfamiliar with his manner (which was, strictly speaking, everyone here but himself). Lack of focus was most common; since crossing over he had been prone to seconds or minutes of, for lack of a better descriptor, blurry thought. Apparently, trying to comprehend two realities at once was too much: his mind had rebelled and would no longer focus on either of them. This was especially frustrating in the middle of conversation. He frequently, and to his embarrassment, had to ask others to repeat themselves for the infuriating reason that he was unable to choose what to pay attention to.
Less frequent (but perhaps more unsettling) was when he fell entirely out of touch with his surroundings. It was like he was simply a passenger in his own body, looking through eyes that weren't quite his own. He supposed that, seeing as the experience also tended to rob him of his empathy, that this could be a valid hypothesis… But that wasn't the point.
The point was - the point was he was frightened. Focus, reason, empathy: he felt as if he was losing himself to this universe. Like it was determined to take what didn't belong and mold it as best it could into what did. And as much as he loved Rosalind, as much as he treasured her like the sister he could have had (had had, could have been) -
He wasn't ready to die for her.