Jujutsu Kaisen: I Can Travel Back in Time - Chapter 45 - 39 She Who Must Not Be Named !!! Escapes!

…but it seems pretty doable.

Turned into a vampire with no political backing, wealth, or power, Dylan immediately tries to become the strongest there is. Facing numerous dungeon breaks and a coming invasion of unknown origin, Dylan must do everything he can to fight back. In the process, Dylan tries to make the world a better place in his way, by taking control of as much land and women as he can. Watch as Dylan amasses power and influence among monsters and humans and rises to the top in more ways than one.

An Individual from Earth finds themselves in the Shinobi World, equipped with a Scientific System. From that moment, he delved into scientific research far ahead of its time.

After the brutal loss of his beloved grandfather, Liam Hunter embarks on a harrowing journey into the heart of the Dark Forest, known as the Forest of Kyrell, with a singular goal: to gain the strength necessary to honor his grandfather’s memory and to never lose anyone dear to him again. At just ten years old, Liam is thrust into a world of darkness and malevolence, where he endures four grueling years of training and transformation. In this shadowy realm, he is reborn as a fierce warrior, driven by a relentless desire to eradicate every demon and ultimately confront the Demon King, Emrys himself. To achieve his formidable goal, Liam must forsake any emotional connections that could weaken his resolve. The once vibrant and joyful boy is transformed by his trials into a cold and unfeeling combatant, hardened by the harsh realities of his quest. This is the story of Liam Hunter—the last wielder of dark magic—whose journey through darkness and sacrifice will shape him into a force of vengeance and resolve.