Toaru Majutsu no Index - Volume 16, Chapter 3: The Duel to the Death between Entirely Different Monsters. Saint_VS_Saint.

As a cultivation genius who has achieved a new realm every two years since he was a year old, Wang Ling is a near-invincible existence with prowess far beyond his control. But now that he’s sixteen, he faces his greatest battle yet – Senior High School. With one challenge after another popping up, his plans for a low-key high school life seem further and further away…

A great demon king who came from another world to conquer Earth. To save the Earth, Li Luyou could only first take care of this great demon king… a little girl proclaiming herself Her Imperial Princess.

- Description from Novelupdates

After a vacation, when she returned to her country she caught her fiancé cheating. She angrily left and disappeared.

Five years later she returned with her talented kid. Afterwards, her son participated in the piano competition. Unexpectedly her son actually came looking for his father.

“The camera on this side, take me to take a look! My name is Xiaoxi my mommy is called Tang Siyu and she’s very pretty! I’m four and a half years old this year. I’m looking for my father, you probably look like me, please be sure to contact me, oh!”

After that, he was gone from the front of the camera again and said, “Oh, I’ll wait for you!”

In the background, a woman became mad. A few days later, a mysterious man came to their doorstep and claimed to be Little Xi’s father.

Tang Siyu looked at this tall and handsome man, who her son was a carbon copy of, and then became angry.

Five years ago, the bastard who pinned her down was him?

- Description from Novelupdates

Witnessing her fiance’s derailment with her own eyes, she married a “poor and poor” poor second generation.

The next day, jewelry, diamonds, haute couture clothing, luxury cars and mansions were received softly.

He is a domineering president who is cold-hearted and black-bellied in front of others, and he is also a three-good man who spoils his wife, loves his wife, and loves his wife.

 …

Rumor has it that his cleanliness allergy makes him never touch a woman, but she is a complete exception;

Rumor has it that he is an ascetic man who is so indifferent to strangers that he is extremely gentle in front of her;

Rumor has it that he is generous and neat and never cares about others. After his marriage, he overturns countless vinegar jars every day…

Her married life: sweet, sour, sweet, sweet, bitter, salty;

His married life: Chai, rice, oil, salt, sauce, vinegar, vinegar, vinegar, vinegar, vinegar, vinegar, vinegar, tea.

- Description from novelbuddy