Doomsday: I Obtained A Fallen Angel Pet At The Start Of The Game - Chapter 2

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

At some point in the 21st century, the Christian God stopped listening to the prayers of humanity. Monsters with colossal strength and endurance began to emerge and humanity entered its darkest period.

“How did a perfectly fine magic world invested by ghosts?”Aya looked at the ghosts in front of her silently and raised her hand to cast a spell.She came to the past and wanted to change the tragedy written in the history books. But how did these ghosts come with her too?Ah, will she cause early destruction of the world?Uh......“Teacher, if I tell you that I didn't mean it, would you stop being angry?” Aya trembled when she looked at the man in front of her.She didn't meant to offend him!“Oh?” Her teacher looks back and smiled faintly. Did she think she could escape after provoking him?“Ah, ah, ah....”Aya swore that she didn't mean to provoke her young teacher. But it seemed that it was inevitable?QAQ

After breaking up with his girlfriend, he accidentally acquired a genius system and rose from there against the heavens, becoming invincible..

- Description from Novelupdates