Some people theorize this is actually part of the 'Midori Dies' series by Dr Yamero - Sensei there already killed himself due to losing Midori after realizing he was forcing his denial of the truth into Momoi, who in turns denies the fact that Midori is dead by pretending to be Midori, before finishing with Momoi turning into SAIBA (T)ERROR, who then also dies... and then it was Yuzu who denies that the rest of GDD is dead by pretending to be Momoi... So this could very well be a continuation of that: Niko denying the fact that Sensei was already dead by pretending that he is still alive.
