MTL - Mythical Tyrant - Chapter 1 Rebirth

Criminal Psychologist, Su Xiao Pei, who was an leftover woman in her modern life, was informed by the God Of Marriage, Yue Lao, that her destined lover was in a car accident, his soul was sent to another world. Su Xiao Pei was ordered to bring back this strange man who was connected to her by the red string of fate. Otherwise, she will live the rest of her life in loneliness, with no one to support her.
But how does that man look? No idea.
What’s his personality like? No idea.
What does he do for a living? No idea.
Can she not go? Of course not.
Su Xiaopei, who believes in all things logical has run up against a serious wall this time.
The bottom line: This is a story about a modern female psychologist who has traveled back in time and an adorable warrior as they talk about love and solve crimes.

- Description from Novelupdates

Cale Virel was just a normal office worker.He was bored and tired of his life, waiting for it to end.And then—Bam!One night, two robbers targeted him!And instead of surrendering, he fought back!Though, in the middle of doing so—PHUCK!He got stabbed and died...He didn't regret it though.After all, he's not really afraid of death anymore.And so...He rested in peace..........Or so he thought!Cale Virel—“Huh? What the fuck?”He woke up as a young slave named Kaiser in a different world!And given another life he didn't ask for again—“Fuck this shit!”Cale, or should I say—Kaiser—“Ugh, whatever.”Decided to live it... By just doing whatever he feels like until he dies.

Working in a big factory for several years, Wang An, who was prematurely aging, accidentally obtained a cheat that can earn experience. The improvement of his skills brought him unexpected surprises.

It turns out that some things are not just legends.

Lightness kung fu can really make people walk on the snow without a trace, and fly over the walls.

Vajra is not broken, it can indeed produce the power of vajra, and become the body of vajra, invulnerable to swords and guns.

Congenital qi, grasping iron into mud

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Brushing experience does not rely on simple repetition, but requires continuous learning, summarization, and comprehension.

- Description from novelbuddy

"When will people understand.... I'm only half insane?"