I remember awhile ago you mentioned possibly either removing or changing the status effect applied by ghosts. My idea is that, since the ghost possesses Liam to apply the effect, it would affect gameplay in ways that make it seem as though the ghost were making attempts to take over Liam's body. Like making the slider shaky, or even have it struggle away, so its harder to keep lined up with the heart; likewise, perhaps during the timing minigames the indicator won't turn yellow, so it would skip from red straight to green. Maybe some changes to the more unique interactions too, such as the "hold spacebar" portion for the werewolves go down slower or even add a little to the bar for each thrust, or a second purple slime could jump onto Liam with a lower struggle meter. All this is done by the ghost with the purpose of getting Liam to fall unconcious so that it can take over his body without having to struggle against him for control.
Now I don't know how hard to implement this would be, and it definitely sounds like a lot of work; however, if you do think it sounds like something you want to add, then you can always add in specific interaction changes after the main changes. If you want to be extra you could add exclusive animations for failing interactions with this status effect, but if that sounds like a lot of pointless extra work then no pressure. Of course, if you like the idea of the changed animation but don't really care for the status effect itself, then you can always just add some secret scenes and make the rest of the effect something mostly unnoticable, like taking extra damage or something. Ultimately, I just like the idea of the possession status effect actually making it feel lime Liam has been possessed by a ghost.