This is my current theory for the game:
My current theory, is that it's some form of experiment by a secret organisation. I mainly think the experiment could either be either to create changes in the personality in an individual (In this case Sensei) and to control his mind; or to combat the effects of a mental illness, likely schizophrenia, in order to try and save Sensei from that very condition. Of course, the setting of this experiment is taking place in an alternate reality, with both Sensei and all of the other characters connected to it, likely by different machines which keep their consciousness within this reality. This would also explain the constant references to wires, as all of them could be connected to the machines which keep them trapped in there. An additional point, it would also explain why the girls can't get pregnant. This is because while their minds are connected in this alternate reality, their physical bodies are not.
I've heard that people think Sensei has some form of mental illness, such as schizophrenia, but maybe the organisation is actually attempting to cure it or else cause it. Or maybe they want to develop mind control techniques, in an alternative reality setting which they can simply carry on resetting the world on an unaware person for the sake of convenience. If he were to be suffering from some form of personality disorder, it's safe to assume those personalities could be entirely different from one another, which seeing as current Sensei is nothing like old Sensei, and there is potentially a next Sensei when the current Sensei is lost, it would explain why they are so different. Each personality would then progressively become more evil, as it can be assumed that his mental illness is becoming worse and less stable (Judging from the happy events and world resets). Seemingly the worst that the old sensei did was give detention to the students, especially Yumi, and obviously this sensei has done far worse than that.
It would also explain why when Sensei does lose control, such as when he kisses Yumi and when he has thoughts of killing people, it is a more evil and less controlled version of himself. He has no memories of these events, because in his mind he was another person, another personality in which he has no control over.
As well as that, it explains why Maya is desperate for the older Sensei to come back. The people are all trapped within this alternate reality, potentially a new version of Sensei could destroy both himself and the world. The current Sensei is a lot darker than the old Sensei, which is why she both mistrusts him, and partially blames him for what's happened. Yet she does understand it isn't entirely his fault, she knows it is her responsibility to somehow fix the impossible.
Next, the organisation may be good or evil, and either can greatly affect the rest of the theory.
If the organisation is good and they are trying to cure Sensei of whatever illness he has, then possibly when Maya prays during a world reset, her thoughts directly travel to the workers in the organisation, they listen to her warning about the world breaking and reset it, ensuring that both the world and Sensei are safe. She has stated multiple times she does not believe in god, and yet she prays anyway and her prayers are answered to reset the world. This could indicate that it is people who are controlling the reset, and not a 'god'. But of course, this causes malfunctions and Sensei temporarily loses his mind as they are not yet able to stop or cure whatever mental illness he has. Whenever Sensei's personality changes, this could be simply the schizophrenia taking control and attempting to destroy either Sensei's remaining sanity or the world. Moreover, the different 'Users' may be various workers in the organisation taking direct control of the situation, in order to save Sensei. The evil 'God' or whatever he is that is referenced quite a few times, could be a metaphor for the root cause of his mental illness. It could be a symbolisation for trauma, or the schizophrenia that is keeping him in this state. And of course, this evil god makes his life hell inside this alternate reality, because it is the very reason that he is there in the first place. So in a way, Sensei is himself that being, and he is slowly destroying himself. Which is why if the organisation is good, they are doing this experiment to save him.
If the organisation are mostly evil, then I think they are attempting to control Sensei and damage him beyond repair, or else develop a mind control technique which they could then use on people in the real world. And of course seeing as this is experimental technology, the alternate reality breaks because they can't fully control it. Maya can be assumed to be a 'good guy' and here to try and save Sensei, but she has to ensure that Sensei does not understand what is happening or he would truly lose his mind, and her resetting the world is simply buying time until she can find a more permanent solution to the entire situation. Maybe she knows someone inside the organisation that is on her side, and they implement the reset for her, but of course seeing as they don't have full control over the experiment by themselves this would explain why each reset can be very different from the last. Alternatively, the organisation could simply be creating the resets themselves until they have completed their objectives, which is to truly control the mind of another person (Sensei), or to create something else entirely with his consciousness. In any case, I think the latest characters will have a very large part to play in relation to this part of the theory being correct.
But with writing all of this, I have not yet completed the most recent updates, and my thinking may be massively different in the future. This is just the general picture of what I think could be happening
