I Became the Little Demon in Leading Role's Family - Chapter 305 - 315 Dad, How Did You Get Here?

In short, MC inadvertently created a world, but as the creator of the world, he did not know the world at all. He should have lived here like a fish in the sea with some plug-ins that MCs always have. But now he is even stumped by the bugs in the instant world. Luckily, in this world he has found his shadow guard, or his lover? So the daily adventure is getting not so boring…

- Description from Novelupdates

Ethen Cole travels to an era where everyone battles with pets. In a world revived by spiritual energy, danger and madness run rampant. Humanity relies on battle pet masters to establish bases and unite for survival.Before the college entrance examination, Ethen Cole is framed and expelled from school, losing his chance to study at the Battle Pet Academy. Just as he feels despair, the Battle Pet System for battle pets activates.“Ding! The Blue Riolux has evolved into a Emerald eyed Riolux!”From then on, Ethen Cole begins his legendary career as a battle pet master.

The interstellar boss, Zi Yi, has come back to life.

This legend tells the tale of the protagonist, Kuroki summoned to protect the demon king from the hero.

Kuroki, unbeknownst to him, suddenly came to another world. He was summoned by the demon king, Modes. The territory which the demon king overrules was in the midst of being destroyed because of the hero. He had no choice but to bow before Kuroki.

“Please save us, Savior Dono!”

Kuroki nodded, deciding to save the demon king due to an unexpected turn of event.