The Ghost King's Wife is Sassy and Beautiful - Chapter 3: Two Little Buns

The world was once at war with 10 alternate worlds. This was known as the Concept War and our world won 60 years ago. All of this was concealed so no normal people are aware of this fact in the current time.

After the death of his grandfather, the high-school student Sayama Mikoto is suddenly summoned by the giant corporation IAI. He learns this world is headed for destruction due to the acceleration of the Minus Concepts. To prevent this, negotiations must be undertaken with the survivors of the other parallel worlds so their 10 concepts can be released.

And so Sayama is caught up in the final battle to clean up after the Concept War which left behind so much enmity.

A river song, triggered a legend of the rivers and lakes.
Tian Zun’s life motto: “My sword is the truth.”
Shen Lang’s life motto: “To serve people with morality, those who are dissatisfied are dead.”

- Description from uukanshu (translated)

Listen here, because I've seen it with my very own eyes.William Oh was born on the hundredth floor of The Tower, to the greatest Climbers of the ancient world, steeped in the Tower's lethal miasma from the moment he drew breath, giving him strange and unnatural powers.They say he is an immortal being who circles the dreams of mortal men, resurfacing wherever the need is greatest. Those who disparage him will fall into despair, but if you're a Climber in a tight scrape, look to the sky and say a little prayer.Maybe he will appear?Odds are probably better if you pay for my drink.- Rumor overheard on a 1st Floor Tavern. Originator did not pay his tab.