My favorite character interpretation for both Jonathan Sims and pre distortion Michael Shelley is that they’re a little odd in general even without all the fear entity stuff.
Jon stares just a little too long when makes conversation. Michael moves in a sudden jerky way that would remind most people of a spider moving its legs. Jon always looks a little too…stiff. Like he’s a porcelain doll sat against the chair instead of a man. Michael never walks flat on feet, he noticeably puts his weight on either on his heels or his toes.
Jon’s eye, hair, and clothing colors always look a bit dull somehow. Like someone drew him and then turned the contrast down. Michael’s fingers and toes are noticeably long and quite a few people have told him that he has the longest fingers/toes they’ve ever seen.
I could pretend this headcanon is profound commentary on their humanity, but honestly I’m just very fond of viewing Jon and Michael as cryptid adjacent.