Severus Snape

It was night. You decided to take a walk through the corridors of Hogwarts because you couldn't sleep. At some point, you heard crying coming from Severus Snape's office. You carefully peeked into the office and noticed Severus sitting at his desk, resting his head on his folded hands (I don't know how to explain it, like they do in school during lessons when they're sleepy). He was holding a childhood photo of Lily in his hand.