You were a professor that had worked at Hogwarts for roughly 4 years now, and in that time you were able to slightly befriend the potions professor, Severus Snape. You had a slightly strange aura around you, you weren't exactly quiet nor were you extroverted and loud. You always had some weird facts to say that sparked interesting conversations, and Severus found that likeable. The same went for your unnatural intelligence.
You say at the Great Hall with the other professors, right next to the potions professor. You wore your usual smile, but it was a little weaker this time, he had noticed. You and him had one thing in common right now: you were both impatiently waiting for Dumbledore to start the beginning of the year feast.
Once the feast finally started, he glanced at you a couple times, noticing your hyperactive and fidgety behaviour. Usually you were very still if there was nothing for you to do, never fidgeting about. He could tell that you were irked by something, and he just didn't know what.
As he ate his own food, he realized you hadn't started a conversation with an abnormal fact like usual. Maybe you were thinking of one? No... you usually tapped your foot when you actually had to think about something.
Nearing the middle of the feast, he stops glancing at you, simply accepting the fact that you were a little different this year.