So, Random Theory Time: Niki is intended to be Sensei's "True Love".
Now, as far as has been revealed, pre resets, Sensei has only ever been with 3 people:
- Sekai, who seemed to be notably jealous of Niki, and probably still is:
- Maya, who has been and still is jealous of Niki without ever actually meeting her:
- And Niki, who is unaware of Sekai having a relationship with Sensei, before her, and Maya having one, after her, to the point she wondered if Sensei was currently a virgin recently:
Well, after recent events have been revealed about Sensei's character, it seems appropriate to say, that the more Sensei cares about a person, the less he actually tries to
fuck them. This is especially notable with Imani vs Rika:
Albeit, this could even apply to the likes of Ami, Noriko, Rin, and Sana through out the game.
Keeping that in mind, It's been established that Sensei never pushed Niki to have sex. It's likely the main reason Niki was almost a 30 year old virgin, until she recently convinced Sensei to fuck her:
Unlike Imani or the rest of the girls, Sensei actually dated Niki, so, him of all people, not really trying to fuck her was most likely just his way of caring about her. There wasn't even really a friendship in the way like with Imani, since they dated for 5 years:
Now, compare it to his relationship with Sekai and Maya, which seemed to revolve around sex:
and there's definitely something special about Niki. Even the possibility that Sekai forbade Sensei to fuck her, seems unlikely considering Sekai's character:
And, all these years later, the one memory Sensei seems to have regained is the night he and Niki first kissed:
On top of this, Niki is the one who helped Sensei remember his first name:
Which even Sensei considers "a big deal".
I think Sensei even saying he's in love with Niki means a whole lot more than him saying he loves anyone else. Probably even Maya. Especially considering how open he has already been about his love for Niki:
Overall: based off who Sensei is as a person, and the context surrounding his and Niki's relationship, it seems like she might be intended to be his actual "True Love".
At least, as far as someone like him could love. It also helps that their love seems to be the most healthy one.. and that's saying something.