I Can Only Become Stronger by Taking on the Demon King's Loan Sharks

Aike arrives in this world as an unregistered adventurer. Knowing nothing about magic or swordsmanship, he becomes the lowest-ranking E-class adventurer.

To make this otherworldly soul willingly offer up his own, the Demon King fills the lowest-level dungeon with powerful monsters, forcing Aike to sign a contract that trades his soul for a chance to survive.

Every day, he is also teleported into the Demon King's arena to fight in cricket-fight-style duels for the Demon Kings' amusement, as payment on his debt.

These days, the debtor calls the shots!

If you owe the Demon King three years of your life, you're the one in a hurry. But if you owe the Demon King a hundred years, he'll be begging you not to die!

Aike decides he might as well borrow more. The more debt, the less it weighs you down. Time to leverage up!