One Piece: Don't Worry, I'm a Doctor - Chapter 77: Master Vir’s Class Begins!

I became a professor in a game by accident. To make matters worse, I even messed up the difficulty settings. Now, I’m stuck playing on Hell Mode. A world on the brink of war with the Demon King. An Assassin Department where mu*der is legal… as long as you aren’t caught. I thought I’d have to claw my way through just to survive in this wretched place, and that was the case at first. But nowadays… “No matter how hard I try, I can’t be like you, Professor… How do you do it?” “Please… become our god.” “What do you know? What is it you know? Why do you make me want to live…?” One by one, everyone at the academy began to obsess over me.

He Lang died by his own hands for the sake of his imperial younger brother’s ambition, whom he loved. He was offered to be reborn in exchange for giving up his past romantic feelings. Reborn without the burden of his romantic feelings, he brings with him a manual to new worlds. He wholeheartedly followed the instructions of the manual to complete the tasks, not knowing that the originally slag gong was blackening…
He pleaded to his affectionate Emperor brother to release him, he pleaded to the paranoid prisoner next door, but until the end he remained baffled.
In the end, he discovered that the full name of the manual was – “Slag Shou Cultivating Manual”
Σ (っ ° ° °;) っ!

- Description from Novelupdates

[mafia, crazy love, abusive love]She was reborn, returned to the age of 18, when she already possessed a colossal fortune. In the previous life, she was executed on the street and died tragically merely due to a dangerous man she'd encountered once.After being reborn, she decided to change her fate. As she pondered how to avoid him, she unexpectedly discovered his name on the list of beneficiaries of the charity.“Can I kill someone?” She asked her assistant.“No. The law binds you!”So, to survive in this life, she tricked him back home. Initially, she believed it to be a means of repayment.Until one day, she felt his gaze become terrifying. She saved him, but accidentally led him down a more terrifying path. Everything had spiraled out of control…When they meet again, he is already a terrifying demon. With blood on his face, he forced her into a corner and said, “Be my mistress, or let me be yours.”She threatened him with a knife, but he laughed even more brightly and held her hand, saying, “You're afraid of me? Ok, I'll teach you how to hurt me the most.” And he guided her hand to hurt himself.She suddenly understood that she should have left him alone. He was injured, bleeding, but still laughing.She said lovingly, “I am indeed afraid, but I don't deny that I love you...”

Leon is an average high school student who likes to watch anime and read novels.
He's about to cross the street, only to be greeted by a truck and died.
But, he got reincarnated as Uchiha yet dead again because Itachi killed him.
Leon got reincarnated again as the grandson of the recovery girl.
He got kidnaped and tortured by All For One.
After his third death, he got reincarnated as a son of Bibi Dong.
In this fourth life, he wants to change his fate to become the strongest.

Note: Please read the tag before reading.
- English is not my first language, so there would be grammatical mistakes in this story.
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