I have a feeling the new teacher is just the MC's brother or something, and this is just a misunderstanding. I mean they sort of look alike, and the teacher did thank the MC for helping him to be able to get that job.
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After reading ahead, I just find it funny now how the author is just trying to trick us into thinking the brother is actually sus by having him smile maniacally every few panels
So brown haired dude is going to rape green haired guy too now...
And the main character's creepy brother probably put a tracker on his phone...
The main character and green haired guy need to run away, just move somewhere all at once and tell no one.
I like how Megu's reaction was bassically
Megu: Wow, that really WAS dumb, well heading I'm out yall, night.