Okami Wa Nemuranai - Chapter 27.10-11

Protagonist travels between different anime worlds to right wrongs and uncover his reason for being along the way.

In his past incarnation, Lu Xuan was the youngest Celestial Lord that the universe has ever seen!
An accidental rebirth brought him back to a thousand years before, where the Earth had just begun its spiritual reawakening. When he stepped onto the way of cultivation for a second time, he swore to rewrite all injustices suffered in his past life, and defeat all enemies that dare stand in his way!
Let invincibility be his cultivation and the path he treads. In this life, it is his destiny to be invincible!

The maniac who was crazy about all kinds of fields such as military and steampunk had been reincarnated.

However, his father was King Sejong the Great?

The mania-wise king and his crazy maniac son.

Along with the ministers, and countless humans who were getting exploited.

Even today, the night of Joseon was filled with the light of overtime.

The past life Ji Anran: “Geng Yan, let’s get back together.”

Geng Yan, who was dumped: “I refuse. You have powers anyway, and you can live well without me.”

After rebirth, the weak chicken Ji Anran: “Geng Yan, let’s get back together.”

The dumped Geng Yan: “I refuse.”

Ji Anran, lying dead: “I have no power, you don’t care about me, just let me get cold1.”

Geng Yan: “… …” The unsuccessful Geng Yan can only take away the weak chicken, one cannot put sand on the wall2 Ji Anran.

Later… what about the ordinary person without the strength to truss a chicken?! Who’s the guy in the day?

- Description from Novelupdates