Are there any characters in this game that can be possessed? I have acquired all the necessary skills and attempted to possess Alice, but when I look at the image and the time, the perspective does not change to Alice's. The “attempt possession” option is not activated.
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You have to be directly interacting with a character to possess them. If you want to force a specific character's possession, move to them on the map, use the 'Hosts' menu to select them, press 'interact with next period', then advance the time. If the random rolls didn't have them leave, you should be interacting with them (their character image is in the top right) and be free to attempt the possession.