This game has quite interesting lore, actually. It seems mainly based around an entity that I shall designate herein as the Oculus (as it seems omnipresent, or at the very least can tell what is going on). The Oculus is a seemingly godlike entity, able to make timeline changes, other universes, or simulations (depending on which realm we reside in). I believe that it is another universe or a backtracked timeline due to the number of things within it that serve no apparent purpose, and the events of Mrs. L. (see below).
I'm uncertain why the Oculus has edited our reality. Whether for pleasure, energy, or ritual purposes seems the most likely. Of these, pleasure is the least likely. The fact that this universe has events that cause pain to the protagonist (the saucer-eyed doll, the stolen locker. Oculus, Latin for eye.) seems to be against the goal, especially because, with our limited meetings of it, it seems of sound mind and body. Though, if the entity has such power as to reverse a timeline or make a new one, it's quite likely they have predictions of it being resolved. So pleasure is still not all that unlikely. Then is energy, perhaps sexual or romantic energy between entities within the realm, which may feed the Oculus somewhat. Then finally, ritual: self-explanatory. Your actions, in some way, are letting some ancient god or beast out, which shall benefit the Oculus.
Of the people who seem aware of the Oculus's presence, there are three (as I believe; add more below if you know of any). Mrs. L, Maxine (somewhat), and Cyberia (possibly). Mrs. L is obvious. she has developed an attraction to the Protag and is wearing provocative clothing, ruining his other romantic chances as such, to the Oculus's displeasure. Then, Maxine. I think she has some awareness, though whether she is aware of its causation and not just its effects is possible, but with her personality, unlikely. Then Cyberia. Of all of them, this is the most tenuous. But I do feel, as an AI absorbing all the knowledge it can, she must know some knowledge. And if not now, her rising importance in the story may mean that she will find out sooner rather than later.
In conclusion, of the facts we know, distilled: the entity Oculus, with its unimaginable power, has edited, changed, or made reality for esoteric goals, adding people (or possibly just editing their fate. Jacklyn may have existed in the original reality, but she never crossed paths with the protagonist) and changed existing ones. For example, Flora: I doubt she naturally feels attraction to her sibling—possible, but with the descriptors of her in the original reality, I think she was more disappointed. Not many know of their meddling, of which three (as I believe) seem somewhat aware on a spectrum. (Though, if any of you know anything more, add it below!)