to add to the theory that Niki is Sensei ture love is the fact that it might be the only relationship that he 100% consented to. Sekai was gromming him so it dont really counts has a relationship and with Maya it been hinted a lot that she was taking advantage of a broken Sensei.
Noriko has said a few times that the relationship with Maya was fucked up and Maya has never disagreed or argued that it wasnt. Sekai relationship was also very fucked up. but with Niki it look like it was just a normal healthy relationship.
Sensei has a werid view on sex where he finds it hard to bond with someone or get close to them without having sex with them he even told Io this. this is most likly because he was groomed and it messed up his views on sex and love.
so the fact he had a normal teenager relationship with Niki where he loved her without having sex is a big deal
Noriko has said a few times that the relationship with Maya was fucked up and Maya has never disagreed or argued that it wasnt. Sekai relationship was also very fucked up. but with Niki it look like it was just a normal healthy relationship.
Sensei has a werid view on sex where he finds it hard to bond with someone or get close to them without having sex with them he even told Io this. this is most likly because he was groomed and it messed up his views on sex and love.
so the fact he had a normal teenager relationship with Niki where he loved her without having sex is a big deal