Quick Transmigration: The Male Lead’s Sister Helps the Wicked Supporting Female Go Wild

[Girls' love + a half-baked System (not much use) + one-on-one romances across multiple books + a little silliness + both leads are virgins + the clever wisdom of a wage slave + a female supporting character who's both good and evil]

Qing Yu, a sharp-minded wage slave from start to finish, and Jiang Yuqing, a female supporting character in multiple worlds

Qing Yu is bound by a System and has to enter various little worlds as the male lead's older sister, raising the female supporting character's affection for her.

Book One: The Domineering CEO and Bai Xiaohua (Complete)

The domineering CEO, dressed to the nines, puts an arm around Bai Xiaohua and says to his former unattainable love, Jiang Yuqing:

“It's getting cold. Time to make the Jiang family go bankrupt.”

Qing Yu picks the perfect moment to step forward, flashes a lopsided Nike grin, and says slowly:

“Little brother, let me tell you a secret.”

“Grandpa left all the shares to me.”

The CEO's shocked-face emoji

System: Affection increased. Earned the ability to foresee the plot for half an hour.

Book Two: Youth on Campus and the Good Girl (Complete)

Who says you can't have youth and experience what it's like to be young at the same time?

Unless you've gone through your senior year of high school twice.

Poor-me emoji

System: Affection increased. Earned the ability to foresee the plot for one hour.

Book Three: Doomsday Disaster: Surviving with Ten Billion in Supplies and a Villainess (Complete)

Book Four: Making Money Through Farming: Eating and Drinking Well with a Villainess (Warning: Sichuan dialect) (Complete)

P.S. Lots of worlds to explore!