I Raise a Demon King in My Rental Apartment

Ai Jia transmigrates to a continent of magic and becomes a good-for-nothing mage with affinity for every element but mediocre magical power.

While everyone else pursues forbidden spells capable of destroying the world, he is obsessed with developing automatic dishwashing spells and temperature-controlled barriers.

Only after joining the Disaster Investigation Squad does he discover the crushing truth:

The so-called “world-ending flood” was caused by his cat knocking over a glass of water.

The “meteorite from the heavens” was a bottle his cat knocked off the table.

The “endless thunder” was his cat excitedly racing around behind the litter box.

And the legendary Demon King of the Apocalypse, whose projection is as large as a small town and whose yellow, slit-pupiled eyes gaze down on all living things, is none other than Nuomi, his calico cat left behind in his rented apartment.

Right now, the fanatical cult of the Apocalypse is summoning the Demon King, while the armies of the continent are assembling for the ultimate battle.

Ai Jia stares at the familiar figure in the crystal ball and falls into thought:

If he tells them now that the only way to save the world is to tire the “Demon King” out by playing with a cat teaser, is it still in time?

P.S. This is actually Nuomi's diary.