Freddy Stern, a twenty-one-year-old cashier, has lived a plain, albeit harsh life. Having been orphaned—twice—he's spent the last ten years working and staying out of trouble. His only aspiration is to save enough money to become an archhuman. His dream gets the jump on him when he barely survives a near-death encounter and finds himself in possession of 1% Lifesteal, a bizarre talent with numerous contradictions and just as many uses.

Melvin Murphy is your average everyday teen... until he finds the System. Melvin has normal problems. High School. Tests. Trying to find a girlfriend (and failing... miserably). But one day he awakens with access to a System that governs all magic. In his attempt to summon a teacher to show him the ropes, he botches the ritual and accidentally summons a magic-wielding girl named Kalliphae. Sure, she's powerful and deadly. A femme fatale who's more intimidating than even the most popular girls at school.

Ilea likes punching things. And eating. Unfortunately, there aren’t too many career options for hungry brawlers. Instead, the plan is to quit her crappy fast-food job, go to college, and become a fully functioning member of society. Essentially—a fate worse than death.

Nathaniel's bus ride was supposed to be just another boring commute. Wrong. Now, he, 23 fellow passengers, and a corgi named Biscuit, are stuck in a "Hell Difficulty" Tutorial, battling monsters and leveling up to survive. Easy difficulty, anyone can handle. Normal difficulty, you've got to put up a fight to get by. Hard difficulty is where only the tough ones last. And Hell? That's where you have to be a bit out of your mind! With his terrifying talent for mana manipulation, Nathaniel decides to invest every stat point into mana.

Fight, survive, adapt, and rely only on yourself. That is Derek’s creed and what's got him through the System Integration on Earth. Everything changed when the System came. Cute bunnies and beautiful butterflies became savage killing machines. Then the Invaders arrived with a single goal: to obtain ownership of this new habitable planet. War has raged ever since. None of this mattered much to Derek, aside from making living a little more perilous.