The entire game is all just a Dying Dream.
- Semi-confirmed, it's Adventures In Coma Land.
The girl in the flashbacks is a younger version of the boy's stepsister.
- Only in the most technical sense it's the stepfather/adult!Adam's daughter.
The stepfather pushed the boy off of the cruise and into the ocean.
- Confirmed by the ending.
Adam is transgender.
- Jossed, the girl we see in the flashbacks is the stepfather/Adam's daughter.