[Slightly hardcore] + [A huge number of self-created academies and students] + [With both angst and sweet moments] + [Daily life/battle]...

Thirty years ago, the Seventeenth Joint Campus was destroyed by an unknown force, turning the once prosperous academy into a desolate ruin. Our forefathers fought desperately during the catastrophe, sacrificing their lives to give their descendants a chance to survive. However, the survivors still wander among the ruins, lost, helpless, and uncertain of the future.

Just as despair was spreading, a firm voice rang out:

"Reconstruction, revival, revenge."

Guided by this brief yet powerful message, the students of Campus 17 wiped away their tears and rose again. They rebuilt their homes from the ruins, unearthing buried scientific discoveries from the depths of the rubble, etching the tragedy into their hearts and transforming past pain into motivation for progress. Beneath the wasteland lies not only a shattered civilization, but also revelations powerful enough to change the future.

Thirty years later, when a similar disaster struck another school known as "Children's Eden," the students of the Seventeenth Campus resolutely raised the blade of revenge. They were no longer helpless survivors, but fighters who had overcome the shadow of death. With thirty years of accumulated experience and the strength forged from the ruins, they would safeguard hope and reverse their fate.

"The past belongs to history, but we remember it."

"What is now ruins, we will rebuild."

"The future belongs to hope, and we create it."

"Hoshino-kun, from now on, you are my dog. The only answers are 'yes' or 'woof'."

Hoshino's time travel was not ideal.

The original owner of this body had more than 40 lives on his hands, which led to him being caught red-handed and forced to become his female boss's lackey.

Even worse, the original owner of this body had signed contracts for three demonic powers by taking out loans to repay other loans, and he had only five days left to live after arriving.

The immediate priority is to sign a new pact with the new demon, using the power to offset the cost.

A hellish start, but thankfully there's a system.

Hoshino stared at the entry: [Forget Your Roots: If you possess a certain authority beforehand, killing the corresponding demon or monster will grant the contractor 50% of the demon's authority.]

"If I borrow 50% of the power and then kill the demon, wouldn't I become the new demon?"

Hoshino slapped his thigh: "The price is off, isn't it?"

"But how can I obtain 50% of the authority and usage rights?"

"Demon's lackey? Eh—Eh?!"

that's all.

Hoshino shamelessly and ingratiatingly acted as the devil's lackey.

He quickly forgot his roots and became a demon hunter after receiving the contract.