My Sister Had No One to Rely On Until I Transmigrated

[One Heroine] + [Urban Slice of Life] + [Book Transmigration] + [System] + [1v1]

Lin Ze, a 25-year-old social elite and top student, transmigrates into the world of a book he skimmed in a flash, becoming a cannon-fodder male supporting character and the son of one of Jiangcheng's top families.

But he isn't the Lin family's biological child. A mix-up at birth led Lin Wanrou and Lin Ze to be switched.

The head of the household has no biological son, and Lin Ze is the only boy in the Lin family. The original Lin Ze dislikes Lin Wanrou and does everything he can to drive her away, eventually causing her to turn evil and become the book's biggest villain.

The woman, now consumed by evil, acquires the Lin Corporation and relentlessly crushes it. In the end, she captures Lin Ze and tortures him to death.

Then the System appears. Completing its tasks will let him return to the real world, but he doesn't want to go back to his old life of drudgery. If he fails to complete the System's tasks, heavenly lightning will erase him outright, so he begins taking his time as he works through them.

To preserve his lavish life as a rich second-generation heir in the Lin family and earn the fifty million for completing the tasks, Lin Ze is all in.

The System rarely appears later on, and the story won't feature much System-related plot.