MTL - The Ancestor of Body Repair - Chapter 1420 islands

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♪

Monsters, both human and beast, surrounded him. He needed power to survive this new world... but he arrived as a mortal.One moment William was at work. The next, he was captured by lunatics.He had never believed in the fantastical, but he had no choice after finding himself in another world surrounded by demonic cultivators trying to extract his soul. If he couldn't find an escape, his journey would end just as abruptly as it started.William was inches from death when a benevolent cultivator saved him from that fate. Seeing his pitiful state, the cultivator decided to give him an opportunity in the form of a tool: A system to guide him on the path of cultivation.William would use it to claw his way to the peak of the cultivation world.

A side story series featuring the girls of Kyoukai Senjou no Horizon.