I Became the First Prince: Legend of Sword's Song - Chapter 279

Born of a great family, world shaking genius.

Zhou Donghuang, a man from the Earth, is able to destroy any planet in the universe without lifting a finger. His supreme will can sweep across the vast cosmos in the blink of an eye. And his immortal spirit can depart from his body and wander around the universe!

In Kunlun Mountains lies a circular slate, which brought him back to one thousand years ago…

- Description from Novelupdates

[Have you become more learned today?][Accounting for the capacity of your brain, your study efficiency has been increased to 28 times that of normal.][The remaining amount of energy you have for studying today, 26 hours.][You will enter an exhausted state when your energy is depleted and be unable to obtain new information.][Please relax by using the functions within the system and restore your energy as soon as possible.]With limited energy and the onset of fatigue, the Study Monster had no time to think too much--papers to come!Had the heavens not grant me this system, the unending sea of knowledge would seem like a long night.

After choking to death on a watermelon, Rong Jiahui thought that she would enter the netherworld and be reincarnated.

But when she opened her eyes, she discovered, to her very horror, that she had returned twelve years into the past…

Looking at the beautiful and awkward “little brother” that would be conferred the title of Marshal in the future for outstanding military service, she almost let out a snort of laughter.

She firmly decided to hug the thigh of this little brother, and climb to the top of her life!

The plan was beautiful, but it had just one problem.

Why had this little brother… suddenly turned into…

A little sister…

- Description from Novelupdates