DxD: Scion of Lucifuge - Chapter 198: I Ask of You, Are You My Master?—Artoria’s Battle Begins

Due to an unexpected turn of events, Xia Fei consumed a Super Gene Optimization Fluid that bore no brand, expiry date, instructions or stated its place of origin.
Our story begins here…

Beings that create and control monsters and demons, beings that build and reign over malicious labyrinths, the chosen individuals to possess an overwhelming Unique Skill… They are the Demon Lords.

Xie Lanyin has a beautiful face with white skin so relying on her face to live is no problem. Furthermore, the prince that she marries is a phonophilia (someone who loves voices/sounds).

A handsome man saving a beauty, he lets her sing songs to repay him.

Getting angry and yelling at him, he’s intoxicated.

At night when he wants to sleep, her words are hypnotising.

When he doesn’t want to sleep, her words become the best ……

Qin Wang: You think too much, the thing I like best is you as a person.

This is a story of a prince spoiling his wife, until even when he becomes a king, he’s willing to bend back so far that he could even break his waist – it’s that kind of story.

- Description from Novelupdates

The one single goal in life of the Strongest Old Sage is to subjugate the Demon King. In an epic final battle, both of them met their mutual destruction at each other’s hands.

However, the Demon King was not completely destroyed!

In order to destroy the Demon King once and for all; post-death, the Old Sage trains in the World of Gods and reincarnates as the Apostle of the Gods, Will.

In the reincarnated future, the Old Sage had become a legend and his former disciples hold the supreme authority in the world. The disciples had created an organization to oppose the Demon King and an academy to nurture the new generation of Heroes.

Thus the Apostle of the Gods, Will (8 year old), enrols into that Academy of Heroes.

This is the story of a boy on a mission to save the world through epic battles while enjoying Academy life.