Burakku Gakkou ni Tsutomete Shimatta Sensei – Chapter 28

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Rating: 5

At the start of the chapter, the MC finds the Chairman groping Ookuro-sensei’s breasts. It’s revealed here that they’re mother and daughter.

Later, Ookuro-sensei meets up with 2 random girls, and asks if they want to “fool around.” At the end, they’re seen nude together, implying they had sex.