Looking for a Period Romance Where Both Leads Are Educated Youths Sent to the Countryside

The female lead transmigrates into a book, while the male lead's soul transmigrates into another body after being reborn. That's one of the story's highlights. The original male lead was frail and died of fright over being sent away to the countryside. According to the book's original plot, the original male lead should have been reborn in his body, but the modern-day male lead, who died of an illness, got there first.