How the Zergs were Made - Chapter 557 - 558 Nuclear Pulse Engine

Living an unfulfilled life, Zack Gray meets an untimely end–that is, until he’s given a second chance, in a new world, under a new name: “Leon Schoeller.” Heir to the Schoeller Estate, a powerful and prestigious noble family, a life of luxury surrounded by maids and butlers of elite skills of their own awaits the reborn man.[Lord System Activated.]In addition to being blessed with a genius mind and magical talent, the [Lord System] grants Leon supernatural abilities, from empowering his servants, conquering beasts, and even manipulating his mansion.However, as gifted as he finds himself, the world around him is full of lurking threats, forcing him to level up if he expects to keep his cozy life intact.

I became a scientist for an evil organization.…But I’m too competent.

First World : CampioneCurrent - Second World: High School DxDThird World: ???Reincarnated into the world of Campione! Haru Kasugano, our hero slays gods and ascends as the mightiest Godslayer. He battles powerful God-Kings and Campiones, claiming victory after victory. Whatever it is. [Wealth, Power, Beauty] he has it All. Watch him grow stronger as he travels into new realms like High School DxD and the Fateverse, leaving a trail of defeated gods and captivated hearts in his wake.

Failing in his job hunting, Sanada Kyouichirou was hopeless in this society. When kyouichirou had thrown himself towards the bottom of a cliff. When he woke up his body had returned towards when he was in fifth grade of elementary school. He did not want to have any regrets in this life so he had decided on building up an harem in this second life.

The elder sister that he admired, a senior and president of the student council at a school for rich young girls, a strong minded upper classman at school. The poison fang of Kyouichirou who had pretended to be a innocent child attacks those girls.