So. Here's my guess on what the deal is. Judging from what we've seen.
Maya is obviously the starting off point.
Not necessary. In my earlier theories, I was convinced that Maya and Amiokay girl are two distinct characters, with the latter being the original and Maya being the...I don't know, substitute maybe? Amiokay called Maya her better version and Ami in a Happy scene said that Maya is a dream baby, as in being conceived in a dream. What the hell does this make her?
So, Amiokay, if it's not Maya herself, is a starting point. Maybe she's that someone "so lonely it shakes the earth to the core", that Yasu was talking about, someone hanging around Sensei in the aether, some, whose arms are always wrapped around his shoulders.
Something went to shit and she prayed (or something) for a chance to correct it. or something.
Sensei might have been the one who initiated this whole thing.
But what happened? My guess? She and Sensei were dating. Noriko showed up or got involved, due to her childhood crush.
It seems to me, that both hers and Noriko's involvement with Sensei happened in one of the cycles, not in a "reality", if such thing even exist for them. The whole time inconsistencies in their explanations seems to indicate just that.
Probably wearing the green and white scarf. Maybe by jumping off a building (the first thing you did in the game was jump)
Green scarf significance is that Maya(?) was wearing it when Sensei(?) answered to her confession.
Sensei definitely jumped. He even called himself an isekai protagonist through suicide, because this guy actually knows and remembers everything and just pushes it down.
Explains maya's hostility to Noriko.
All we know is that Noriko "ruins everything" given time. That's it for now.
Personally, I think that Noriko messed up some of the things Maya was trying to do in pervious loops to bring back Sensei/keep him in a loop/whatever it is that she was trying to do.
Also, there might have been an intense rivalry going on between them when they were kids. Such feeling may occur when your rival in the same exact situation as you, basically your reflection.
Hence my theory that Sensei was in love with Maya's sister (and she knew), that coincidently also was Ami's mother (he was at the scene of the accident and even removing metal that pierced her body). Sensei's uneasy feelings towards his brother were mentiond at some point, inferiority complex, i think.
so, a new world. But something went wrong. The Sensei wasn't *HER* sensei.
According to Yasu, since nobody dies, they just hang around in aether. So, whatever her/Amiokay/Sensei did, Sensei's body was alive and well after a "suicide", but his soul was "on rotation", I guess.
She's gone through multiple iterations of the same events, keeping "sensei" at distance because it's not HER sensei, despite looking like him.
I think her attitude and general strategy to keep fending off "Sensei" bitten her in the ass, when she got a scarf as a present from him and realised that it might have been the real Sensei.
But because it's her world that was created to save the Sensei, the rest of it molds around him. Like the girls getting insta-attached to him, him getting away with pretty much anything etc. All the while Maya watches helplessly, knowing that it's all her fault.
But I guess OUR sensei is special. and Maya is about to flip out completely. This is her personal hell, but suddenly she's no longer the nexus of it all.
The game ends when Maya finally comes to terms with her loss, maybe by falling for "our" sensei. Or something to that effect.
Thats my quick theory.
I think that a deal was made with one of the "Gods" (wired Tree-computer, most likely) to make Sensei's body a vehicle for a God to experience things, with a random soul "driving" the body around. Now it's a real Sensei's turn.
Sensei used to take tuitions, while being in a relationship with Niki, and used to live in the old part of the town
Maya and Noriko were his students, and both of them developed crushes for Sensei
Ami's parents die, which forced Sensei to move to the new part of town to take care of her. He stops taking tuitions, and disappears from the lives of Niki, Noriko and Maya.
Sensei takes a new job in a school, Maya somehow ends up in the same school, and somehow Sensei and Maya end up in a relationship
I wonder if it all happened in "reality", single cycle, or between several cycles.
Maya is his subconscious, who is slowly helping Sensei to heal his mind.
She also said that she wants him to keep doing what he's doing, stop asking questions and just enjoy an endless school year. I think she's just afraid that he will snap and his soul will go on rotation again, with someone else taking his place for gazillion more cycles, before Maya will be able to do whatever it is she's trying to do.
She is scared of Noriko, because Sensei must learn about himself on his own, and Noriko telling him what happened might destroy his mind.
So far, only Maya causes him to trip, though.
HOPE is the intact part of his mind, HOPE has locked out Sensei's memories as a means to save his mind. The "wire god" is the machine Sensei is hooked to in the real world keeping him alive.
What do you think of the angels? Yasu wants to become one and I remember Maya/Amiokay mentioning that she's an honorary angel.
The game will end once the Sensei successfully regains his memories, and comes to terms with what transpired in the events leading to his suicide.
I think part of the reason Maya wants him to stop asking question is to prevent him from gaining memories, something she straight up admits.
I think that is due to some of "real Sensei" iterations (assuming there were some before this one, which I think there were) completing the whole cycle and jumping from a roof again, restarting this whole thing.
Speaking of memories, I think he's got them alright (Maya seems to think so), he just pretends (or rather convinces himself) that he doesn't. Maybe the Wire God connection blocks them (maybe that was part of the deal, something Sensei wanted himself), but every time they go out of synch, memories resurface, or/and the opposite: every time memories resurface, they go out of synch.