Death March kara Hajimaru Isekai Kyusoukyoku (WN) - Book 17 - 17-14. Changing World 3

Three years into Qin Yu's marriage, his wife and in-laws all hated him.

Transmigrating into a fantasy world, starting as a typical rich and handsome guy, he has a useless main character fiancé, a sister who knows the future plot, and a distant cousin who is the reincarnation of his nemesis, the Nine Heavens Mysterious Maiden.He becomes the final boss in a female-oriented novel, forcibly killed by the plot?Although he has a system that allows him to become stronger by binding with geniuses, Jiang Minghan states that as a gentleman who likes to stay calm and friendly, he just wants to be good to others and doesn’t want to be a villain.To avoid the fate of being overpowered by the female leads in the future, he can only walk further down the path of a villain.But unknowingly, when did he become the source of darkness, disrupting the eternal heavens?

“If magic is power, then I'll build my own.” - Adrian.When a genius tech developer dies from overworking, he awakens in a world ruled by magic, ancient empires, and mythical beasts.But unlike the natives who manipulate elemental mana, he is granted a mysterious technology system that lets him reconstruct modern and futuristic tech.Armed with the knowledge of his old world and this game-like system, he begins to revolutionize the magic world. But his rise threatens the very foundation of society, drawing the attention of kings, mages, and forbidden powers that ought not to be offended.As nations clash and secrets unfold, one question remains:Can technology coexist with magic… or will one destroy the other?

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 –