Counterattack System appeared when I'm already At The Mahayana Realm - Chapter 20 - : 100 Ways to Make a Man Take the Initiative

Bai Aoxue, the best mercenary in the 21st century, is accidentally sent back to the Chengxi Dynasty in Great Continent due to an explosion in her mission, and trapped in the first daughter of Prime Minister. After her rebirth, she is set up by her father to marry the 5th prince Jun Yeyan who wears a mask all day long.
In the face of bloodthirsty enemies, discord between brothers, collusion among courtiers and invasion of enemy state, can Bai and Jun resolve the crises? What will happen to their political marriage? How will the fierce battle for the throne end?
With many twists and turns, the book brings you to experience palace revolution, love and hatred thousands of years ago.

- Description from Novelupdates

Tired of the intrigue in the big city and the face of the boss, tired of working overtime every day and earning thousands of dollars, Zhou An returned from the big city to the small fishing village where he was raised, and lived a leisurely life!

Plant vegetables, grow flowers, and thousands of acres of fruit trees!

Walk the dog, feed the cows, the ranch is thousands of miles away!

Deep sea seafood, shallow sea fish, fishermen catch!

Cultivating mountain streams, grazing cattle and sheep, and fragrant fruit trees!

In the bright spring, the teenagers wandered freely, and Zhou Ande was surrounded by mountains and rivers, and lived a leisurely life!

- Description from novelbuddy

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

Before the disfigurement, everyone loved Ling Chunan. After the disfigurement, Ling Chunan became a plague that everyone avoided. He was held on captive by his own agent afterwards because he was so ugly now, desecrating his love. Finally, Ling Chunan chewed himself to death because he was starving. After his death, a thing that claimed to be the counterattack system 098 found him.

A long time after, a certain counterattack system of a host with a 100% success rate posted a message in the System Forums.

《Emergency Help Request, my host is a masochist! He won’t be happy if every meals doesn’t have meat, and if he doesn’t have meat to eat, he will start to gnaw himself! How to treat this illness?!》

Great God : No need. I have a fast recovering ability. I will let him bite me.

- Description from Novelupdates