My Sister the Heroine, and I the Villainess - Intermission, Chapter 0.2

In the end, war couldn’t be extinguished. But, there was a transformation. Even in the heart of a worthless accomplice in murder who was indifferently continuing his task, there was a transformation. The massive weapon “Object”.

This was a weapon that changed the whole definition of war. An exchange student named Quenser, who was dispatched to the battlefield, met at the base a girl with a strange aura. The girl, dubbed “Elite”, is the pilot of “Object”. The near future. This diminutive boy had come to take on the role of standing up against the strongest weapon “Object” for the sake of the girl. This was the motive for their first meeting.

Li Yuanqing transmigrated and became the crown prince of Northern Kingdom. He was sent to the borders, after his cultivation and meridans was crippled, because he refused to marry a princess and was not allowed back into the palace ever.

Just then, the Hundred-fold Sign-in System was activated!

Outside his house in the Wilderness, he signed in and received 100 Replenishment pills!

Beside the lake of the Wilderness, he signed in and received 100 Marrow Cleansing pills!

Among the warriors of Myriad City Kingdom, he signed in and received 100 Heavenly Skill manuals!

…

Li Yuanqing had thought that if he just signed in silently and received the hundred-fold reward, he would be able to watch over his younger sister until she became the ruler of the kingdom and until he became invincible.

But he had never thought that one day, the queen of Myriad City Kingdom would come to meet him!

“I am willing to use Myriad City as my dowry. Will you marry me, Your Highness?”

Li Yuanqing did not know what to do when he looked at the queen smiling beautifully before him…

The simulation is over, and the entry is obtained: a showdown!

Looking at this entry, Zhao Meng was stunned.

“How should this term be used?”

“Hey! Here’s a wounded fox!”

…

A few years later, a woman who looked like a fairy appeared in front of him, and said:

“My lord, I’m here to repay my favor!”

This book is also called “Starting from Transforming Monsters”

- Description from novelbuddy

As childhood sweethearts, they were made to engage under the manipulations of their families. It involved having to to live in the same room and sleep together.

One night, she is accidentally made drunk, and in his delirium, he kisses her only to realize he enjoys it. From time to time, he would sneak a kiss on her, but his “crime” is eventually discovered in an accident. After being accused by her, he says with a smile, “You are my wife, why can’t I kiss you?”

The two people’s daily routine is full of bickering and mutual discrediting of each other.

Although he claims to disparage, he actually cares intensely about her. He feels crazily jealous when she is close to other men, to the point of tying her to his side, so that she becomes exclusively his.

- Description from web