1. This can be totally up to you! The fae realm is deeply entrenched with magic so characters who are sensitive to magic can both sense something's off or not, depending on whether or not their magic works or it glitches. It's your choice whether you want your character to feel it for a certain prompt with one character and then not for another.

2. Simon might only pick up a blank slate for any of the people that might show up, but you can also pick up actual memories if you want to play around the idea of Simon mistaking them for real. For the creatures, all of them will be filled with rage and grief, as well as some remnants of magic on them.