Keep a save file at the start of Day 4. From there, you can branch to any route.
The game takes place in the town of Kanazawa, where the protagonist, a transfer student, moves to attend a new high school. As he navigates his new life, he becomes friends with a group of students who are all connected by a series of strange and supernatural events. The story explores themes of friendship, trauma, and the power of human connection. shiny days walkthrough guide
You cannot save directly on a choice screen. Save immediately before a scene with choices or immediately after. Keep a save file at the start of Day 4