Devil Slave (Satan system) - Chapter 14 Do Not Bow...

Name: ParadoxSpecies: Snake, ?Description: A tiny snake with great potential.That was who I was. That was what I was. A tiny snake with great potential. The sole creation of the Great Core.It was just us, the Great Core and I, tucked away in our little corner of the World Dungeon. Together, we hid from the bad-things and the Coreless of the world outside - safe from the horrors that would consume us.Until, one day, the Coreless found us. Until they tried to steal away my creator. Until, with no other option, I swallowed the Great Core that had made me.Only after that did I become what I was always meant to be.At last, I became the Great Core's Paradox in more than name.[The Endless Cycle] began.Thus begins the story of a little snake zealot and his journey to greatness.

A serious accident caused the protagonist’s brain to have an unusual mutation. This changed the brain development that it opened the door to a mysterious universe. Not only he obtained a ‘god-like’ powerful telekinetic control and mental perception, he also had an abnormal analysis and memory capability comparable to super computer. Having such super brain, his rough life began.

Brain development progress 10%…….20%……50%….80%…. …100%

- Description from Novelupdates

Once upon a time, an Alchemist Grandmaster from the World of Immortals accidentally took possession of a playboy, who hailed from a rich and powerful family, and became a student in the middle of his midterms.

The world is terrorized by the powerful Black Witch who has been sealed in the moon. Every ten years, the night of Hexennacht arrives and a chosen witch must battle the Black Witch in hopes of finally defeating her.

As the current decade’s Hexennacht approaches, a mysterious girl named Kagami Kagami arrives and meets Horinouchi Mitsuru, the daughter of the previous Hexennacht representative.

It takes place between Kyoukai Senjou no Horizon and the City Series, two other series by the author.