You must sleep in your own bed, located in the first room, in order to change into ghost form. If you are in ghost form and wish to return to your body, you can use the other bed. However, you cannot sleep if the Grim Reaper is nearby or if you can hear its heavy breathing. I think i need to make a book under the table in first room and put all the mechanics and rules of the game. I put the mechanics of the game on the wall, if you see the drawing in the wall that is the mechanics but the thing you say about you can't leave your body using the other bed is not included in that drawing.
Thanks for pointing out any issues you encountered, I will work on improving the UI and the details of the mechanics of the game.
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Ah! I just assumed it was an issue with the two beds close together. It would be good to be able to switch forms in any bed just to avoid too much back-tracking. I have to admit I only really got as far as I did because I saw you outlined the game "rules" in a response to a comment on the game page: I don't think they necessarily need to be described in the game itself but some sort of run-down somewhere would be handy.