If the player eats Buck, a shadow called The Follower will follow them for 7 minutes. They'll get sound cues such as an ominous noise when the screen shakes and music when The Follower is nearby. If the player is touched by The Follower, they'll die, but if they survive for the 7 minutes, The Follower will leave them alone.
Also, Folly mentions in multiple conversations with other NPCs how she watches over their dreams, and she often torments them with their fears.
This are some instances where someone in the game is stalked, so if I missed something, please add a comment!
If the player gives a kitty to the Unpleasant NPC a crunching noise plays, implying that Unpleasant ate the cat. Buck, who resembles a cat, can also be eaten by the player
In Jeremy's Domain, Jeremy will grab a player (or if there's only one player, an NPC), take them away and put them in a cage. The remaining player(s) have to save them but if the timer runs out and the kidnapped player/NPC isn't saved, they will die.