YUGIOH: It's Time to Duel! - Chapter 1: What is this!?

Jerry traversed across worlds and arrived in a Beast Summoning era. In this world, everyone could summon their own pets. Darkness was looming, and the world was in turmoil. Relying on the power of their summons, many shrines plundered the resources at every corner of the world like tyrants. But when everyone else was summoning adorable pets that could help them in battle, Jerry discovered that his summoned pets were a little different. Other people's pets are all kinds of beasts, but Jerry summoned gods from Greek mythology! King of the Gods, Zeus, “Master! I, Zeus, is at your command!” Athena, “I will fulfil all your requests, master!” Poseidon, “I will conquer this sea in the name of the master!” In constant summons, step after step, Jerry became the supreme ruler of this world!

A normal guy gets hit by a truck and isekai'd. Why? Because trucks are apparently some cosmic loophole. He decides to be a dungeon, because it sounds weird and interesting to be one. Is it? Let's find out.

Stella Wilson, a nice rural lady who went to New York to pursue her Veterinary degree. Also, she works part-time as a pet sitter to a three little cats. Her boss, Alice Adelson instructed her to keep the cats away from the next-door neighbor Sebastian, the billionaire. An Alice cat, however, managed to escape from Stella's care and make the way to Sebastian's property, where caused her trouble. Stella is caught by Sebastian while trespassing his property.Sebastian informs her that she must keep the cat away or else he would punish her. Sebastian has already made the decision that he will going to own her and has stated that she will be responsible for the payment. But it's not in monetary value that he's looking for.

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♪