
Im changing my theory. New guy seem to be a good guy. So hes gonna be used to be killed or for something else.
I think whats gonna happen is that she marry him. Junpei will tell her to do it because its the best case scenario for her.
The letter we see at the end is a letter that she get sent to junpei after she dies. Because ofc shes gonna die first with her health problems.
So we get a bittersweet ending of everyone staying alive, but not ending up with the main couple
Probably wasnt self defense because the guy wasnt a danger anymore or something. Gosh im so use to seeing in stories 'it was self defense', when their is totally ground to argue if it was actually self defense in real life.
like us as reader 'yeah hit that bitch' but in real life the legal system goes probably would be 'was this really necessary'