I Became the Youngest Summoner in the Strongest Guild - Chapter 76

Wang Yi gets a key, opening a door in 2022 will lead to 1982, and opening a door in 1982 will return to 2022.

Two very different great eras appeared before him:

Abundant dietary protection, developed industrial products, miraculous medicines, and explosive information, this is 2022.

Simple folk customs, rich wild resources, scattered antiques, and treasures of the age, this is 1982.

Traveling between these two eras, Wang Yi didn’t think much of it, he just wanted to live a good life.

- Description from novelbuddy

Reborn and returning, he possesses medical skills, can practice immortality, has a slave who is the king of killers, and a maid who is the school beauty pursued by everyone. Even casually taking out a piece of trash can shock the world. His return has set this world ablaze.

In a world teeming with Titans, Colossals, Gigantic Monsters and Kaiju's, Erian who reincarnated makes his living collecting scraps of low-grade Defective Genetic Serum, realised he transmigrated along with his system.

Follow Erian as he grows to become the strongest Disaster Grade Titan with the help of his Titan System!

The story begins as our female lead wakes up in a strange room and an unfamiliar body. She realizes that she has travelled back in time and her twenty-two year old spirit is now trapped in the body of a six year old girl. This girl child is the third daughter of Ning Guo’s Prime Minister Li and his seventh wife. Her name is Li Qing Luo and because her mother was originally from an entertainment house, Prime Minister Li and his other six wives treated them badly.

Her first day in that world, the whole family gathers to test the talent of the three daughters. Qing Lei, the eldest, is talented at playing the zither while Qing Fei’s calligraphy is incomparable. Everyone anticipates A’Luo’s failure as she had not exhibited any talent before, but that six year old child recites a famous Tang poem. The entire family is surprised that Qing Luo is able to write such a profound poem and her mother later tells her that Prime Minister Li is so harsh on his daughters because he needs to rely on them marrying well to secure his future. Qing Luo begins to study qin, qi, shu, hua (zither, chess, calligraphy, and painting) but hides her skill because she does not want to be sold in marriage to some prince or court official.

Six years later, A’Luo is now twelve and leaves the estate for the first time to participate at a flower viewing banquet. This is a special banquet because the Five Most Eligible Bachlors of Feng Cheng will be in attendance (there’s actually a more elegant name for them). These young men are: Crown Prince Liu Jian, Fourth Prince Liu Fei, the young An Qing Wang Liu Jue, the son of Prime Minister Gu Gu Tian Xiang, and the top scorer of the Imperial Examinations Cheng Si Yue. A’Luo sneaks off and almost falls into a river, but is saved by a handsome young man. Because he glanced at her bare legs a moment too long, A’Luo calls him a pervert, tries to push him into the river and runs off. The young man only laughs and vows to find her again.

- Description from Novelupdates