MTL - Cub Keeper - Chapter 624 Playground for the little cubs (below)

“I'm going out to do something, so I can't take care of you any more. You can go down the mountain and have fun. But if you can't find someone who matches your Innate Pure Yang Body in three years, you're finished!”These were the last words the old man, who was Lionel Yeager's teacher, threw to him before he vanished. Meanwhile, having mastered most of his master's skills, Lionel Yeager went down the mountain and took his first step into civilization for the first time in years.With his unparalleled medical and martial arts, he sets forth on a journey, befriending new allies and crushing all the enemies that stand in his way, as he attempts to resolve his Pure Innate Yang Body constitution, and cultivate to the top of the world!

Travel to the world of One Piece?

They come, the security;

Became Don Quixote Rossindi?

Forget it, it can’t be reopened;

But after realizing that he had eaten the fruit of silence, the little boy became restless.

Fruit of Silence, this is one of the devil fruits that can compete for the title of “the most useless” in the world of One Piece; it is only a little better than Chopper’s “Everyone’s Fruit · Common People’s Form”!

“Dover, you said you are a devil fruit wholesaler, why do your family eat all kinds of weird ones?”

Facing the bewildered little Dover, Rossindi patted his forehead.

“Forget it, let’s practice domineering hard.”

- Description from novelbuddy

Damian, a Centurion of the Punishment Unit of the Baroque Kingdom. “Damn it.” Just once. If I were given just one more chance… ‘I would have truly conquered the battlefield with these guys.’ At the age of 30, he closed his eyes on a nameless battlefield. But when he opened them, he found himself back 17 years in the past. And this time, he had a perfectly functioning mana core that could wield magic. ‘This time.’ I will rise higher than anyone else. I won’t be swept away by the turbulent times. ‘I will conquer.’ Damian, who has returned to the past, wields his spear toward the world.

A man who was once called the world’s strongest agent ended up becoming a teacher after his retirement, to train a new generation of agents. After many years of training his disciples, he was killed at the age of 60 by a secret organization’s ruse and was reincarnated in another world with his memories intact. Though he was surprised by the existence of magic and the strange species in that world, he quickly adapted to his condition as a newborn and took advantage of it. He acquired special magic and gained a massive amount of strength thanks to his rigorous discipline, in order to reach his goal: Resume his career as a teacher which he left halfway through in his previous life. This is the story of a man, who, based on the memories and the experiences of his previous life, became a teacher who travels through the world with his students.