There are fanfictions where Snape has a more complex reaction. He might see a glimmer of Lily in Harry's eyes, which makes him feel a strange sense of protectiveness despite his hatred for James. So he tries to distance himself from Harry, not wanting to get involved, but at the same time, he can't help but keep an eye on him secretly.
He could also be shocked into momentary silence. His first sight of Harry might bring back a flood of memories, both good and bad. Maybe he freezes for a second, his mind racing with thoughts of Lily, Harry's mother, and how things could have been different. Then he quickly composes himself and tries to hide his inner turmoil behind his usual stern facade.
He could feel a sense of guilt. Snape has always had a role in Harry's life, sometimes as an adversary. Knowing that Harry has these scars which are a result of Voldemort's actions, and Snape being involved in some way with Voldemort in the past, he might feel responsible on some level.
He might be filled with intense jealousy and pain. Snape has deep feelings for Lily, so seeing her with James would be like a dagger to his heart. He could feel a mix of anger towards James and self - loathing for not being the one with Lily.
He might be initially shocked. Snape has this complex relationship with Harry. He may try to hide his concern behind his usual cold exterior, but his eyes might give away his surprise.
Snape might be suspicious at first. He could think Harry is up to something mischievous or perhaps trying to find a weakness in his teaching. Maybe he'd keep a closer eye on Harry during class.
He might be initially shocked. Snape has a complex relationship with Harry, and seeing those scars which are a mark of Harry's past and his connection to Voldemort could stir up a lot of mixed emotions in Snape. Maybe he would feel a pang of guilt, as he has some role in Harry's life due to his connection with Lily.
In a typical fanfiction scene, Snape is standing in the Great Hall during the Sorting Ceremony. The first - years are being called up one by one. When Harry's name is announced, Snape's eyes immediately dart towards him. His face hardens, and his grip on his wand tightens involuntarily. The air around him seems to grow colder as he stares at Harry with an intensity that makes some of the nearby students shift uncomfortably.
He might feel a mix of anger and sadness. Anger because James was often a bully to him, and seeing fanfiction that might depict James and Lily in a positive light could stir up those old resentments. Sadness because he loved Lily deeply and lost her to James.
He's probably furious. Snape has high standards for student behavior, and smoking is definitely not acceptable in Hogwarts. His face might turn red with anger, and his eyes would narrow as he glares at Harry.
The teachers at Hogwarts would have mixed reactions. McGonagall might be a bit hesitant, not fully trusting Snape's intentions but also knowing that Dumbledore has some level of trust in him. Flitwick might be more open - minded and wait to see what happens. And the other dark - arts - related professors or those with a more complex view of Snape might be intrigued to see how this situation unfolds and how it might impact the balance of power within the school and in the wizarding world as a whole.
Severus could feel a sense of guilt. He might think that he should have been there to prevent it, especially if the abuse is related to the wizarding world's problems that he has some knowledge or influence over. He may then start to take steps to help Harry get out of that situation, like using his skills in potions to heal any physical or mental wounds.