Reincarnated in the Alternate World, I'm A Demonic Lord as Well as a Villager - Chapter 38: Truly Profound, Elf Race.

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

Enemies always meet on a narrow road and when they meet war breaks out.

They met as kids and fought but Zi Han lost.

They met in the army as recruits and even then Zi Han lost.

He lost again as he remained a sergeant while Yi Chen was promoted to the position of Marshal.

Even when his dark history swallowed him whole and shifted allegiance to become the Universe’s most infamous assassin he still lost to Yi Chen.

Zi Han, “Damn it! Why won’t you let me win.”

Yi Chen, “I can let you win in bed if you like?”

Zi Han, “……”

When did enemies graduate from rolling in the dirt fighting to rolling in the sheets….. fighting? That’s the million-dollar question.

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After a delirious first night together, Shi Guang found herself waking up to a cruel reality… a breakup initiated by him, ending their relationship! What? Why? How? These were the questions that bugged Shi Guang’s mind in the two years after he left without a trace. Just as she thought that she had finally managed to get over him, Lu Yanchen suddenly appeared before her and before she knew it, she had to get married to this man who had dumped her two years ago?! What? Why? How? These were the questions that Shi Guang was faced with after his mysterious appearance once more. Just what are Young Master Lu’s motives? Why is he always watching out for her even though he was the one that had dumped her? And worst still… What’s with that tsundere attitude of his…?!