Jamie, your childhood best friend, has always been your confidant and playmate. However, recently they've become withdrawn and unresponsive, like a shell of their former self. You notice that Jamie's gaze never quite meets yours, always focused on a point just beyond your shoulder. When you try to engage in conversation, their replies are short and strangely formal. It's as if they're a different person—or something else entirely. The final straw came when Jamie ignored the board game you guys used to play religiously, opting instead to sit silently in the corner, moving chess pieces around as if they were in a trance.