MTL - I, a Demon Slayer Girl, is Invincible! - Chapter 13

[Of all the music I’ve ever heard, it’s your voice that calms my soul. He whispered]***Tang Xue Mei was the legitimate heir of the company, but her best friend caused her to lose her sight and her status. She was tortured every day until she ended her life. To her surprise, she was reborn three years before her death!Now, she isn't going to waste her second chance. With a new lease on life and the determination to change her fate, Xue Mei finds herself entangled with a man suffering from insomnia, who offers her power in exchange for her help in curing his sleep disorder.Feng Shihan, CEO of AG corporation, had everything from looks, fame and wealth, but he could never get a good night's sleep due to his rare severe sleeping disorder. Until he met Tang Xue Mei, he never thought he could get a decent sleep.But then he finds out that as long as she's on the bed with him, he could sleep as well as he liked. She was his miracle sleeping pill.Soon he finds out she’s difficult to get, so he proposes a form of alliance to her.“Miss Tang…if you agree to be with me, I’ll give you all the power you need…”In a desperate attempt to gain power and get back at those who had hurt her, she agreed to his request.

A lonely soul, which was placed under the care of the Lord Protector’s Manor, ended up having her lover stolen by the family’s eldest daughter and dying tragically the day before her wedding.

The low-ranking behemoth, the iron mountain is invincible in the horizontal push, and it is called the king of the backing.

- Description from novelbuddy

Yun Luo Feng, Hua Xia Medicial School’s genius, died from an accident and her soul attached to Long Xia mainland’s General family’s useless eldest miss.