MTL - Comprehensive Manga: The Wandering Ninja World Started From Questioning Payne - v2 Chapter 16 , Straw Hat Luffy! Appear!

Jiang Pengji got something called the Court Intrigue Stream System.
System: “Your goal is to become the most prestigious woman in the kingdom (the Queen)!”
Jiang Pengji: “Okay, System. No problem!”
Years later, she met the target by becoming the most prestigious woman (the Empress).
Jiang Pengji: “Well done, no?”

- Description from Novelupdates

Ronnie, a college student with a boring life has everything around him change when his whole world is turned upside down by a woman he accidentally summons while trying to summon a magical familiar as a game.His peaceful and tranquil days are disrupted as he tries to help her fit into human society while also searching for a way to break their bond.Hell further breaks loose when he discovers that his familiar is indeed the demon queen and mysterious forces start trying to eliminate him for reasons unknown.He struggles to protect himself, adjusting to having a demon queen in his life, and understanding his growing feelings for her.

A sweet yet difficult journey to get his ex-wife back.

She had a marriage contract with him. Her father forced him to marry her because she loved him so deeply. However, he didn’t love her and asked her to sign an agreement, according to which they should split the cost of living, have no children and get divorce four year later. She accepted all conditions because she thought that she was able to melt his heart.

However, after three years, nothing changed. He was still as cold as ice. At that time, another woman appeared. She was his co-worker, and she called him “Brother Chen”. Lu Yao gradually discovered that their relationship seemed to be vague.

What was worse, she was unexpectedly pregnant, and she wanted to give birth to their children. As she believed that he would definitely make her have an abortion, she told him that she was going to divorce him.

To her surprise, he refused to leave her and started to treat her with passion like he never did before. He hounded her nearly every day. It seemed that he realized the importance of her only after he was about to lose her.

And he found that she was so charming when she no longer pleased him and started to live her own life.

A master assassin transmigrates into an interstellar era.