It was a really strange situation for someone to look at an empty space and ask, 'Who are you?'
If it was before the fall, he might have been rushed to the psychiatric hospital, however in this new world, there were lots of strange things that became normal or were becoming normal.
With the introduction of skills, formerly impossible things became normal, and even among those impossible things, there were still impossible skills. And one of them was Jon's skill, 'Moon gaze'
Without being able to see the full description, he was able to spot weakness, see through and scan things. Now, he could see more, and maybe because he wasn't in an already established place where the evolution stages had already occurred, however it wasn't usual.
The usual ocular skill wasn't meant to spot something as someone hiding themselves with space. And especially this level of person.
