What if in the previous iteration MC died trying to solve the case.
Which lead the living heroine to step up but also lead to her demise
Which also made her ghost heroine that sent to past with no memory
Which later met MC and the ghost heroine encourage him to solve the case
But MC died trying to solve the case!
Which lead the living heroine to step up but also lead to her demise
Which also made her ghost......
It's a time loop................
Also The maskman is the boyfriend
Somehow I'm sure of that