Yin-Yang Harmony System - Chapter 285

[By the Author that brought you “Return of the Frozen Player”!]The Return of the Fallen Tower Master: The Revival Era of the Magic Tower

On a certain day, a certain thought came to Japan’s Sun Goddess. ——Aren’t there too many Japanese people being abducted to other worlds? It’s true that the large majority of Japanese are diligent and docile and soft-hearted, which makes them pretty much the best people to ask for favors. “But recently it’s just gotten way too out of hand…… Oh, I’ve got it! Whenever a Japanese person is summoned, I just have to summon an otherworlder!” And now, every time a Japanese person is summoned, princesses and elves and beastmen and whatnot are reverse-summoned. Under the acknowledgement of the government, they begin living in Japan. Today, too, Japan is at peace. And so begins this laidback isekai cultural exchange story♪

Sequel of Allison, taking place about 17 years after the original series.

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)