Clearing an Isekai with the Zero-Believers Goddess – The Weakest Mage among the Classmates - Chapter 16: The secret of Lucy

One night she gets drunk and mistakes the most well-known Mafia boss for a host and intends to sleep with him.

Oh my! What should I do? It’s best to run away!

- Description from Novelupdates

When necromancers perform a great ritual to summon an undead servant, they bring a powerful vampire into their world. And now, their fate is sealed as food, but for Klaus, this is just the beginning of his adventure. In a cruel world where people will do anything for power and immortality, he is already very strong and immortal, so what's left if not start a family and have fun stepping on arrogant people through the way?

{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.**