Sword God in a World of Magic - Chapter 10: Mana

The end of the world is coming, the world has undergone great changes, and everything has changed. Plants, animals, and even insects, as long as there are living things, have mutated.
Become more powerful, and even evolved supernatural abilities, such as chickens and ducks that can fly to the sky, such as cats and dogs that can breathe fire.
But only humans, without any obvious changes, seem to have fallen from the top of the food chain to the bottom of the food chain overnight.
Any creature that can open its mouth to eat can treat humans as food.
But fortunately, this world has not completely killed humans. Gradually, humans discovered that they had the ability to cultivate compatibility with other creatures.
As long as it has a high degree of compatibility with some powerful mutant creatures, it can be used for its own use to achieve the purpose of protecting itself.
Fang He is a person who is very compatible with mutant animals, but it is also because of his ability that he has changed from the strongest to the stupidest.
Fang He, who was reborn, said, “Hmph, this time…”

- Description from novelbuddy

Mizuno Eiji, a siscon high school student, receives the worst news from his older sister: “I have a boyfriend now.”In order to identify the man who stole his sister, he follows her on a date and… sees a suspicious figure watching the two of them as well.That person is Hasegawa Aoi, his classmate who is famous for hating men despite being a beautiful girl!“I can’t believe you are actually a brocon.”“I never thought you are a siscon.”In order to make their beloved sister and brother to break up, the two of them formed a mutual relationship and went on a date as fake lovers while following the brother-sister couple… Aoi kissed Eiji on the cheek.“You’re the only one who is… special.”Brocon x Siscon, two people who shouldn’t be able to get along is actually a perfect match…!?

Synopsis ___________________ Viretta Medlit is a hopeless braggart. One day, she casually boasts to a young man she meets about her unfortunate arranged marriage, only to discover that he is her fiancé. To make matters worse, her exaggerated claims stir something within him. “Are you prepared to face any hardship?” “Of course. If it's for the one I love, I’d even hunt a dragon!” “Then let’s go hunt a dragon. And break off the engagement afterward.” Thus begins Viretta's journey to hunt a dragon… All in the name of breaking off her engagement with a fiancé she actually finds quite agreeable!

”When I tell you to proceed with Plan A, you can’t just ignore it and go with Plan B,” said the king.

”Sure”, she replied; she’ll just go to Plan C then! No biggie.

”If you were told to go eastwards, you can’t just ignore me and go in the opposite way,” the king added on.

”Yes,” she said while nodding. If she can’t go in the opposite way, North and south work fine too.

”You are NOT allowed to have affair with any other men!” the king then emphasized.

”Sure”. She replied. She never has to be the one having affair with the others. Others have it with her.

- Description from Novelupdates