An Eighties-Era Bride Swap? I Go on a Rampage with the Sign-In System

In her previous life, Ji Sisi married Dong Tengfei, a young man from a military compound, and spent her whole life as a wealthy wife with no worries about food or clothing. Her younger sister, Ji Manrou, lost her husband to sudden death on their wedding night. From then on, she was treated as the Gu family's curse and tormented until she died of depression. After living another life, Ji Manrou declares that this time she'll be the one to enjoy an easy life as a wealthy wife! Ji Manrou engineers a marriage swap, leaving Ji Sisi with no choice but to marry Gu Yu, a man doomed to die young. The Ji family raised her, so taking her place and suffering in the Gu household is the best way to repay them. Ji Manrou is confident about her future. Ji Sisi, who transmigrated into a book, doesn't think any of this is a problem. What's a man to her? With a System in hand, she'd rather thrive on her own! But you, stop clinging to me. You're ruining my mood for making trouble. Gu Yu: “You saved my life, so I'll repay you with mine. I'm sticking with Sisi for the rest of my life!”