Childhood sweetheart/high IQ/rescue
This was a carefree life with my girlfriend, but everything started to collapse.
His girlfriend was alive and dead in his arms, but he couldn't find any suspects. His girlfriend's suspicious death made him go back to the past inexplicably...
"Zhaoyuan, what are you hiding from me?"
His girlfriend hid a secret from him, forcing him to explore on his own to explore the cause of his girlfriend's mysterious death and look for suspicious clues.
And after he went back to the past, he discovered more unknown things... And the woman who helped him go back to the past also hid some secrets.
Concept: Even if everyone wants to change the past, time will not be reversed