Yes, this is my issue with Noriko as well.
Ayane is becoming rather calm and aware of how popular Sensei is, and I am certain Kirin has had a significant impact on that (as well as Sensei being just .... not the best person ever....).
Noriko on the other hand is highly obsessive, extremely intelligent and knows exactly how to act and react to appear calmer/nicer/more perfect than she is. Surprisingly Sensei has noticed that (partly) but she spells trouble. And with trouble, I tots am with you there, I mean violence and murder to anyone approaching Sensei aside her.
And that is especially true for Maya, where even Noriko is not holding back in how she feels about her (and neither does Maya, rather surprisingly. Which just means that whatever happened between the two had to be absolutely terrible if someone can get such a reaction out of Maya, who shut herself out of feeling due to the myriads of resets she already had to endure).
That being said, I do believe that it won't be that violent, or rather I hope, cause for all the red flags that Noriko is throwing, she actually became my favorite character (hey, don't judge, I always had a crush for hyper-intelligent punks. The hair is an added bonus on top).
Then again, this is LiL... There is only one HOPE in this game, and he does not share happiness.