The Great Worm Lich - Chapter 275 - Maniac

Over a million years ago, the first human contracted with the first Spirit. Ever since then, Spirit use has become commonplace. Humans used Spirits to carry items and start fires. Eventually, even start wars. Thousands upon thousands of years past and one day, one human did the impossible. He transcended his mortality and ascended to the realm above.

In regards to the MMORPG Cross Reverie, Sakamoto Takuma boasted an overwhelming strength that was enough for him to be called the Demon King by the other players. One day, he gets summoned to another world with his appearance in the game. There, there are two people that insist “I am the real summon master.” Takuma gets slave-turning magic used for summoned beasts cast on him by the girls –

Chang An is a sub-beast who, despite having the talent for the sword, did not have the constitution to support it. And his savior, Hua Yi, is a beastman on the run for his life.

This is a story about how two once innocent children had to grow up in such a cruel beastman world.

- Description from Novelupdates

Seven years ago, after their breakup, he disappeared without a trace.