UBOK.

Overview
UBOK. is a Japanese collaborative project between SDS and RAHU developed in RPG Maker 2000, the latest version having been released in 2011. The game's production was cancelled in mid 2012. It stars Eric, a relatively wealthy hikikomori who, in his bed, explores the realm of his dreams.

The game is known for its medical and skeletal motifs.

Gameplay
In UBOK, the player needs to collect Bones (effects) and 9 scattered pages in Eric's dreams. The player enters the dream world by sleeping in the bed, and saves by interacting with the laptop

There is a debug room accessible from Eric's room in the real world by interacting with the wall on the left of the door. There's also a minigame that can be played using the console next to the TV.

Plot
From the various effects and areas in UBOK, it is possible Eric had some sort of bone complications/surgery that affected him throughout his life, or was a rather sickly person growing up. He most likely kept notes/a journal of his days, which is what you find scattered in his dreams.

Bones (Effects)
Along with the effects, there are also nine hidden pages in the dream world. Collecting all of them triggers one of the two endings.