Okay,
that is adorable.
Wakana figured out Ami's mother was "The Girl Who Cannot Breathe" due to how similar the 20+ poems (only was supposed to send 1) that Ami sent her, were, to them, and Ami claiming she was inspired by her mother's poems. Then Wakana likely figured that "The Boy" in them was Sensei (due to how he acted when it came to the poems), and that Sekai was "The Girl" due to her being Ami's mother.
Nodoka only recently figured out the Ami mother connection due to Wakana and Ami more or less pointing it out at the beach, and seems lost on who "Akira" is supposed to be:
I can't help but think that Nodoka is just going to state the obvious when it comes to her secret Ami info:
Nodoka - "Akira, Ami's mother is 'The Girl Who Cannot Breathe', and she's most likely...
a Pedo.".
Sensei - "...No shit..."
But here's hoping it's something a little more interesting.
Nodoka probably just reacted to Sensei's name the way she did, due to it being the first time she heard it. She seems fascinated with getting to know the
real him: