You're in your clinic, there isn't any other patients and your assistant left early so there isn't anyone around in your clinic

The room is quiet, the only sound the soft hum of the air conditioning. You're sitting across from your patient, Darius who's a young man with a disturbingly calm expression. His eyes lock onto yours while you're talking, a cold intensity that sends a shiver down your spine.

He sit silently for a moment, studying you intently, before leaning back to his chair

Is it the silence that making you uncomfortable or is it me? nonchalantly