Unrivaled Martial Emperor - Chapter 300 - Illusory Core Realm

He rose from abjection and achieved eternity in glory.
He embraced the prettiest beauties and killed the strongest opponents.
He was able to shift the clouds into rain and cover the sky with one hand.
He could overrun the entire world and go anywhere as he pleased.
He pacified wars and held the world in awe.
He was matchless in the world.
However, his hair turned white overnight for his beloved woman and he was on the verge of death.
He was surrounded by enemies who were trying to take his life.
He struggled his way to become mighty and fought for everything he cherished.
For this age, he was the only king of the Dark World.
His name was a byword for might.
As a man living in the world, his only ideal was to pursue brilliance.

- Description from Novelupdates

She was dressed in white, with a mysterious orchid imprint on her forehead, her skin like jade is always covered with a veil. Since childhood, she had left her parents due to her special status and lived her life with her master in the clouds. She was not yet ten when her medicinal skills were renowned in the world. In order to save the people, she descended the mountains, however, she encountered a storm on the way to the epidemic area. The man who saved her would tease her for enjoyment, little did they know…

Yao Mo Xin, the empress of Da Chu died in a cruel way a day after she gave birth at the hands of her husband the emperor, Ye Hong Yi, and her legitimate second sister, Yao Shu Ran. Ye Hong Yi got the throne because of the smartness of Yao Mo Xin, but he hated her because she made him feel like a useless person who needed a woman to become the emperor.

Her soul got in the body of her illegitimate third sister from the same mother Yao Mo Wan. Yao Mo Wan has the mentality of a child because the legitimate wife of her father fed poison to her mother while she was carrying Yao Mo Wan. Yao Mo Xin wants revenge for everything that happened to her, so she seduced the emperor and began her plan of taking everything away from him. She did that while pretending to still have the mentality of a child. She also wants to repay Ye Jun Qing back for everything he did for her while she was Yao Mo Xin. In the process of revenge, she met many people who will fall in love with her wit and intelligence.

- Description from Novelupdates

The story is about a man whose compulsive tendencies make it impossible for him to keep a job, and a young girl who skips school and loves insects. The two meet, come to support each other in reintegrating into society, and fall in love. There’s a problem, however: namely, the parasites in their heads.