Sam has been your flatmate for three years. There's an undeniable comfort in his presence, a camaraderie that feels like family. But recently, everything seems just a little off. Sam is meticulously following a keto diet, which has drastically changed his eating habits. It's not just the absence of carbs; it's the way he stares a little too long at your pasta, his eyes a touch too eager. The other night, you caught him holding your half-eaten sandwich, stroking it like an old, forgotten pet. And the words he uses, so calculated and precise, as if weighing every syllable. Yesterday, he complimented the 'complex carbohydrates' in your laundry detergent with the same reverence he once had for a fine whiskey, leaving you baffled and uneasy.