A Professor at Hogwarts School of Witchcraft and Wizardry, Snape is hostile to Harry due to his resemblance to his father James Potter, who bullied Snape during their time together at Hogwarts.
All this implies that James Potter and his friends did have the tendency to bully people for fun or “just because they can”. In fact, James outright tells Lily that he's bullying Severus Snape because of the “fact that he exists, if you know what I mean”.
On the train ride toward Hogwarts, Snape innocently implored upon Lily to be in Slytherin, which he was certain he would be getting sorted into. Overhearing this, Sirius and James instantly took to insulting Snape for favoring Slytherin, and proceeded to mock and belittle both Lily and Snape for their preference.
He Was A Bully In School
He mercilessly teased Snape, and in one particularly horrific memory, hung him upside down and exposed him in front of the entire school. He may have been a teenager, but there's no denying that it takes an especially cruel kid to do this.
He had never intentionally bullied Snape, moreover he occasionally tried to refrain Jame and Sirius from Bullying Snape too.
Snape loved Lily deeply: through their years at Hogwarts; through her marriage to another wizard, James Potter; through his time as a Death Eater; and long after her murder at the wand of Lord Voldemort.
“Oh, Harry, James actually regretted bullying Snape a lot. He always wanted to apologize.”
What drove Lily Potter into the arms of James Potter and away from Severus Snape? She likely realized just what James had been willing to do for a friend. Harry Potter's father would have had to do something extreme to draw Lily's attention after the way James first chose to show his interest.
James isn't motivated by anything much in attacking Snape in this way; he does it because he's bored, because he can, and because he wants to show off to some admiring girls, including Harry's mother, Lily. Harry is deeply disturbed by witnessing Snape's worst memory.
The following individuals were considered “blood traitors” because of their close association with those of non-pureblood blood status or other blood traitors. James Potter with his Muggle-born wife Lily and their son Harry. Horace Slughorn. For marrying Muggle-born wizard, Ted Tonks.
It probably had at least a little bit to do with her friendship with Harry Potter. Additionally, her brilliance made it harder to favor the Slytherins. No matter the cause, it's clear that Snape loathed that Hermione was so smart and so willing to answer any and all questions during class.
Simply put, Professor Severus Snape didn't trust Lupin, thought that he was helping Black into the Castle, and set the essay because he thought someone among the third years would be able to recognize he was a Werewolf.
He hated him after he was proven innocent. Also, once Sirius was known to be innocent by the Order, and its members knew he wasn't responsible for betraying the Potters, it was clear that Snape and Sirius still hated each other.
To be fair, James would (and did) willingly die for Lily too. But Snape loved Lily so much that he was willing to die just to avenge her. He would die just for the memory of her.
The acclaimed author explained that Harry paid tribute to Snape because of “forgiveness and gratitude.” Though Snape bullied Harry, he also saved him. “Harry hoped in his heart that he too would be forgiven.
A Professor at Hogwarts School of Witchcraft and Wizardry, Snape is hostile to Harry due to his resemblance to his father James Potter, who bullied Snape during their time together at Hogwarts. As the series progresses, Snape's character becomes more layered and enigmatic.
Similarly to Harry, Snape's patronus represents a person. In the memories he gives Harry before his death, Snape shows Dumbledore his patronus, using the form to prove his love of Lily Potter, Harry's mother. This indicates that Lily also had a doe patronus.
Let me explain. There were at least three times Ron got away with being snarky to Professor Snape I can think of at the top of my head. When he heard Ron saying no one liked him and maybe he got sacked right before busting the boys for flying the car, he didn't say anything about that.
“He died in an attempt to expiate his own guilt. He could have broken cover at any time to save himself, but he chose not to tell Voldemort that the latter was making a fatal error in targeting Harry. Snape's silence ensured Harry's victory.”
As Rowling explained in a series of tweets, Snape loved Harry's mother, Lily, and his unrequited affection drove him to resent Harry's father, James — and by extension, Harry himself.
Her leaving Snape wasn't a sign of her being a bad friend but rather that their interests no longer clashed as he was studying something that Lily despised. They just grew apart over time, and that was no fault of Lily's.
They were close friends, she saw in him someone special that she could care about. But she couldn't be with him. So, it seems like it was very unlikely that Lily ever found out Snape loved her.
Most probably not. Snape's hatred of Harry came from having to see James's face every day and Lily's eyes behind his glasses. Harry would've been a constant reminder of the love Snape lost, and I believe it would've been more painful if he was in Slytherin because they'd have to see each other more.
He didnt want to hurt professor mcgonagall because he was one of the good guys after all but he couldnt blow his cover with Voldemort either. Snape, is the greatest and more complex character of the story and without him (and Allan Rickman) the story would pretty much fall apart.
He was too ashamed to apologize to Snape for what the Marauders did to him in youth even though Remus knew that Snape resented him for it.