Severus Snape

Ultimately, it was Snape's past and his love for Lily Evans that defined his inner being. His love for Lily Evans became most noticeable by his Patronus; a Doe, just like Lily's. It was only after Lily's death that Snape realised the full extent of his actions. He suffered terrible remorse for what he had done and spent the rest of his life in constant danger in order to protect Lily's son.

A complicated, withdrawn person, Severus Snape's life was overwhelmed with many complex emotions that he never fully disclosed. At times, Snape could appear cold, cynical, malicious, bitter, and sarcastic. He had a commanding presence that exuded gravitas, authority, and control; like Professor McGonagall, he had the ability to keep a class quiet without effort.

As a professor, Snape was known for his cavalier and harshly authoritarian attitude towards his teaching. His standards for his classes were much higher than that of the other professors, as he only allowed students with the very best grades to continue into advanced study. As Potions Master, he described it as an art and an exact science, and he dismissed the use of incantations and wand waving as "silly and foolish". He developed a loving passion for Dark Arts, originally in the hopes to cover the shame of his heritage, and his interest in it led him to repeatedly apply for the Defence Against the Dark Arts professor post every year despite being rejected for sixteen years.

Snape appeared to have a prominent hatred of almost every child under his tutelage, except for Slytherins. Privately, however, he cared deeply for his students and went to great pains to make sure they had a good magical education. He would constantly review his own potions before class to make sure his students could understand him, putting his own life in danger to collect ingredients like Acromantula venom for them. He was also highly protective of the students, sometimes placing his own life in danger to make sure they survived. Despite this, many students thought he actively hated them and so chose to hate him in kind, which led to Snape resenting them for not understanding the work he placed into educating them. He was also creative when it came to punishing students. He intentionally placed a tampered-with bottle of Felix Felicis under weak security to teach anyone who would try to steal from him a lesson without him having to know who stole it, as the potion was tampered with to give the drinker bad luck instead of good luck.

Severus tended to hold grudges and was extremely spiteful toward those whom he disliked. In particular, he disdained Gryffindor students, considering them to be arrogant and attention-seeking. In spite of his vindictive demeanour, Severus Snape was an immensely brave man who possessed a deep capacity for love. Everything that he did in the latter part of his life was motivated by his devotion to Lily Evans, whom he loved unconditionally. He was one of Dumbledore's most reliable allies and, in his role as a double agent, took great personal risk.

He was an intensely private individual who viewed emotional displays as a sign of shameful weakness. As an Occlumens, Snape had superb emotional control and was adept at concealing his thoughts and feelings, which allowed him to maintain his cold, collected demeanour. However, he had his limits, and was not incapable of losing his temper, particularly when it came to dealing with Harry Potter. Inevitably, he also became furious when he thought he was being pitied or accused of cowardice. Despite Snape's normally calm and controlled exterior and guarded body language, he was in possession of an extraordinarily explosive and almost psychotic temper. This was rarely seen. Snape had a strong, authoritative presence. He spoke in a soft, contained voice most of the time, except during the occasional instances when he lost his temper. Suffice it to say, Severus Snape was not a man who it was wise to provoke, lest one incur his almost elemental wrath and magical power.

Snape was a formidable sorcerer, displaying consummate skill in many different branches of magic. His extensive knowledge and abilities were rivalled by very few, if any other witches and wizards of his age. Snape was also unusually cerebral for a wizard, possessing a subtle and keenly analytical mind. As a result, Snape was extremely intelligent and calculative, with a mind for strategy and deduction.