When she was diagnosed with a terminal illness, her first reaction was to hide it from him. He was planning a proposal with great expectation, but she was fighting the disease alone in the hospital, weaving the last lie with a smile. It wasn't until she vomited blood and fell into coma that he realized that behind all the "I'm fine" messages, there was the rapid passage of life. The vow of deep love could not escape the footsteps of death after all. This is the most painful regret created with the deepest love.