Sister Equals Toy: Mr. Ohguro's Breaking Point

HIgh school girl exclusive r*pe! r*pe! r*pe!

STORY
Inazo Ohguro is not popular with his students, to put it bluntly.
Laughed at and belittled, he gets zero job satisfaction.
This pitiful man has one decent relationship with a student, and that's Satsuki,
the only person who acts like she cares.

"I love Ohguro-sensei's classes. Keep trying hard!"
"Yeah."

But in his bitterness Ohguro doesn't even trust her.

"That little tramp is making fun of me by being so patronizing. She's the worst of all."

One day after school, Ohguro catches a student trying to climb the closed gate fence.
It's Satsuki's little sister Mana. Realizing this, Ohguro's black heart finally bends to madness.

"You little bitch!"
"Wha? Aaaaaiiiiiieeeeeee---!!!!!"