I actually dunno any spoiler. But based on the 1st chapter, it looks like one of them will die? All this are just my own assumption tho IntensifyHEHE
Here I am hoping it was acutally the father writing Satoko's letter after she left with Goto. Her father crying and dying alone because he fvcked up his relationship with his daughter and wife. I am so hoping it really is the father, and not the older Goto reading her letter
Its torturing seeing all this struggle & fights only for it to end in a tragedy