This, of course, hints at one of the most major twists in the entire series: the reveal in the final installment that Snape has been on Harry's side the entire time because of his love for Harry's mother, Lily, who was killed by Lord Voldemort.
Most of the wizarding world rests securely on one side or the other. Snape, however, is outwardly loyal to both, but trusted entirely by neither.
Pretty much everything he did was two-sided. Even in the alternate, Voldemort-flavoured reality we witnessed in Cursed Child, Snape was working undercover. He really was that committed to the double-agent life and, as he himself told Harry, being good at Occlumency was an essential part of the job.
However, Snape demanded of Dumbledore that his love for Lily (his reason for switching sides) be kept a secret, especially from Harry, because of the deep animosity he felt towards Harry's father and his mixed feelings towards Harry (who reminded him of both his love for Lily Potter and her death, and his animosity ...
Snape never exactly "switched sides". He was in the middle of being a triple agent when Voldemort disappeared (his curse backfired when he tried to kill baby Harry). Later when Voldemort returned, Snape simply spun it as he stayed with Dumbledore because Dumbledore's protection kept him out of prison.
But Snape didn't have time to get too deeply into that. Later in the year, Dumbledore revealed that Harry was in fact a Horcrux, meaning that he would eventually have to die. Now, as firmly established, Snape was not the greatest fan of Harry, but that didn't mean that he ever stopped loving Lily.
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.
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.
He doesn't trust Snape as Dumbledore does, but he believes that he can detect any disloyalty. Moreover, Voldemort regards Snape as highly intelligent and therefore ' as a true Slytherin ' a person whose top priority is to take care of himself.
"I regret it," said Voldemort coldly. When Voldemort finally works out the truth about the Elder Wand (albeit incorrectly) he sends Lucius to fetch Snape and then confronts him before killing him off. He confesses his apparent “regret” for having to kill him, twice.
When Snape used his Patronus to lead Harry to the Sword of Gryffindor. But of course, it was not just Harry whose Patronus saved the day.
She knew Snape was working for the Order - everyone in it did. Professor McGonagall knew that Snape was working with Dumbledore. Everyone in the Order did, which is why Snape was actually let into Order meetings - if they didn't know, they'd likely have tried to not let him it.
Voldemort intentionally made six Horcruxes, but when he used Avada Kedavra on Harry, he unintentionally created a seventh Horcrux. Instead of dying, Lily's love for Harry created a counter 'curse' known as Sacrificial Protection and saved Harry.
The final book, Deathly Hallows, explains this. Snape HAD BEEN a Death Eater. He later renounced his connections with that group, but no one besides Dumbledore knew for sure whether he had truly switched sides, or was just faking it. Dumbledore, alone, knew the truth.
Originally, British actor Tim Roth was in talks to play the character. Roth is now recognizable for playing Emil Blonsky or "Abomination" in The Incredible Hulk and later in the MCU as well. But, before that, he was the studio's first choice for Snape and was on board for it.
Dumbledore himself was aware of Snape's actions and trusted him to aid him in his mission. He also shared some information with Harry regarding Snape's true loyalty and role in his plan, but only toward the end of the series.
I cannot deny, however, the fact that Severus was loyal to Dumbledore, to some extent. He responded very differently to Dumbledore than he did to others. He wasn't rude, sarcastic, nor bitingly cruel to Dumbledore as he seemed to be to many others.
Snape calls Lily a Mudblood, Lily tells James that she would never date him because he's an egotistical jerk. Later, Snape tries to apologize for calling Lily a Mudblood, but she's not interested; she ends their friendship due to his association with Death Eaters.
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.
Harry Potter named his son after the character Professor Severus Snape in tribute to him dying for “for Harry out of love for Lily [Potter],”JK Rowling revealed on Friday.
Snape told him to. It was necessary for Harry to take his tears so that he would know what he needed to do to defeat voldemort. Especially since the only other person that could tell him was Dumbledore and he was dead.
Snape's secrecy is revealed to have been a mask and he has sacrificed being well-liked to be able to save Harry, all because of his love for Harry's dead mother: the only friend Snape ever had.
"The first thing Snape asks Harry is "Potter! What would I get if I added powdered root of asphodel to an infusion of wormwood?" According to Victorian Flower Language, asphodel is a type of lily meaning 'My regrets follow you to the grave' and wormwood means 'absence' and also typically symbolised bitter sorrow.
Dumbledore reveals how thoroughly he loves Harry. Harry is brave, and Dumbledore is proud as any father would be. More than that, Dumbledore succumbs to a parent's weakness; he cares more about Harry's happiness and wellbeing than the wizarding world he is trying to protect.
The reason that Lilly's death was a true sacrifice (as in she died though she needn't have) is the fact that Voldemort genuinely would have let her live if she had stepped aside and let him kill Harry. Snape convinced Voldemort to spare Lilly.