Became a Failed Experimental Subject - Chapter 15: That Must Be Tough

I do not own this imageHe was a swordsman beyond compare—cold, calculating, and relentless. A man who chased power not for glory, but to break the fate forced upon him. Betrayed in his final battle, he died with his blade in hand... only to awaken in a world not his own.Now reborn in the world of High School DxD, Nero carries with him a mysterious System that allows him to defy logic:— Steal and evolve Sacred Gears— Accept world-altering quests— Access a store that sells power itself— And shatter the limits of every universe he entersWith the power of his Void-Forged Blade and a will forged in war, Nero walks among Devils, Angels, and Fallen—but he kneels to none.As he joins Kuoh Academy, crosses paths with Rias Gremory and her peerage, and uncovers the secrets of the multiverse, one thing becomes clear:This world, and every world after it, will tremble beneath his blade.

When Viscount Ascham’s House’s eldest daughter, Adele von Ascham, became 10 years old, she remembered everything with an intense headache.

When I came to, I had reincarnated along with the base fortress from my sci-fi game. What’s more, I was in the form of the female avatar I used in the game. All around me was an endless ocean, with no iron, no fuel, no energy, nothing at all! No matter how advanced sci-fi technology is, without resources, nothing can be made. Despite this, the natives use some sort of incomprehensible technology called magic, and there’s not a trace of science to be found. Most importantly, I want to eat proper meals for nourishment, not just survive on IV drips! This is the story of a TS girl surviving in a fantasy world together with a super-advanced but spoiled AI administrator.

{System Online} {System Activating} {System Activation Complete.} {User Detected: Jake Lucas.} * {Main Quest: Grow strong enough to defeat your foes.} *{Warning: Darkness Approaches. No One Is Safe.}* 200 years ago, humanity almost faced extinction at the hands of the werewolves. The world survived, but the cost was unimaginable. Victory was hard-earned—and the price paid is still unknown. After seeing the war wasn’t heading anywhere, the werewolves receded to grow their strength while letting the humans recover. Now, sixteen-year-old Jake Lucas is thrust into a battle he never wanted. Weak, outcast, and haunted by his parents’ brutal deaths, Jake is just trying to survive at Aurora Academy. But when a strange orb activates the Slayer System, everything changes. Quests, skills, and powers that could make him stronger than he ever dreamed. But power comes with a price. With each new level, Jake uncovers dark secrets—about the werewolves, the academy, and the shadows lurking beneath them all. The world is more dangerous than he imagined, and a hidden force is stirring, ready to rise once again. Jake’s only hope lies in mastering the Slayer System—but as the stakes grow higher, he’ll learn the real question isn’t how strong he can become, but *how far he’s willing to go* to stop an ancient evil from being unleashed. **But the system has a final warning: Jake isn’t the only one unlocking power. And the clock is ticking.**