About the Pair

Thanks to Wikipedia for the info. Sorry it if seems to long, not many fanlistings post info on their subjects so here is basics yet relation to this fanlisting. Also links within the info are to fanlistings.

Severus Snape

Over the course of the series, Severus Snape evolves from a malicious and partisan teacher who unfairly punishes Harry and other students he dislikes (while favoring Slytherin students) into a pivotal character of considerable complexity and moral ambiguity. J. K. Rowling has described him as "a gift of a character" Portrayed by British actor Alan Rickman, Severus Snape is introduced in Harry Potter and the Sorcerer's Stone as the first named Hogwarts’ teacher in the story when Harry Potter arrives at the school. Snape is the Potions Master at Hogwarts, though he is widely rumoured to want the post of Professor of Defence Against the Dark Arts. Snape himself confirms the rumour in a later book. At one point, Snape is named as a Death Eater by Igor Karkaroff, but Dumbledore comes to Snape's defence, claiming that although Snape had indeed been a Death Eater, he changed sides before Voldemort's downfall and turned spy against him. Dumbledore assures Harry that Snape's reformation is genuine, though he refuses to tell Harry how he knows this, saying the information "is a matter between Professor Snape and myself".

Towards the end of the 7th year, Professor McGonagall and two other teachers force Snape to flee the school. Voldemort summons Snape to the Shrieking Shack and, erroneously believing Snape is the master of the Elder Wand, has his pet snake, Nagini, kill him. Snape, dying from his wounds, releases a cloud of memories which Harry collects in a flask and then views in the Pensieve in the Headmaster's office.

From these memories, Harry sees Snape's childhood and learns of his true loyalties. Harry observes that Snape befriended Lily Evans, Harry's mother, as a child when they lived near to each other in Spinner's End. Upon their arrival at Hogwarts, the Sorting Hat placed Snape and Lily into Slytherin and Gryffindor Houses, respectively. They remained friends for the next few years until they were driven apart by Snape's interest in the Dark Arts.

Snape became a double agent for the Order of the Phoenix against Voldemort, using his powers of Occlumency to hide his betrayal from Voldemort. Snape felt responsible for Lily's death when the Fidelius charm was broken. Despite Harry's strong resemblance to James Potter, the fact that he was Snape's only enduring connection to Lily (and the fact that Harry inherited his mother's eyes) made Snape protect him throughout the series, despite their mutual animosity. Snape demanded of Dumbledore, however, that his love for Lily, his reason for switching sides, be kept a secret.

Rowling noted in an online interview that because Snape abandoned his post before dying or officially retiring, a portrait of him does not immediately appear in the Headmaster's office following his death. She adds, however, that she imagines Harry made Snape's true loyalty and heroism known in the Wizarding world, and that he lobbied to ensure that a portrait be installed in the office.

Lord Voldemort

He was born as Tom Marvolo Riddle, the last descendant of the wizard named Salazar Slytherin, one of the founders of Hogwarts School of Witchcraft and Wizardry. Voldemort appeared either in person or in flashbacks in each book in the series, except the third, Harry Potter and the Prisoner of Azkaban. Voldemort has also appeared in all the corresponding film adaptations as of present date, except the third. Portrayed by British actor Ralph Fiennes, Voldemort was invented as a literary foil for Harry Potter, the main protagonist of the series, and that she intentionally did not flesh out Voldemort's backstory at first.

Throughout the series, Rowling established that the name "Voldemort" is so feared in the Wizarding world that it is considered dangerous even to speak his name. Most characters in the novels refer to him as "You-Know-Who" or "He-Who-Must-Not-Be-Named" rather than saying his name aloud. In Deathly Hallows, a Taboo is placed upon the name, such that anyone who utters it may be traced by Voldemort or his followers. While Voldemort's given name is Tom Marvolo Riddle the second book establishes that the appellation "Lord Voldemort" is derived from an anagram of his birth name: TOM MARVOLO RIDDLE ~ I AM LORD VOLDEMORT. This is also a play on words, as his name, Tom Marvolo Riddle, is also itself a riddle. In translated versions of Harry Potter and the Chamber of Secrets, Voldemort's original name is changed to accommodate the anagram.

Rowling introduces him as the Dark Lord who has murdered the parents of protagonist Harry Potter, and later unsuccessfully tries to regain his dissolved body by stealing the eponymous Philosopher's Stone. While writing the book, Rowling established that Harry Potter's parents have been killed by the powerful Dark Wizard Lord Voldemort; but for some reason, baby Harry survives when Voldemort tries to murder him with a Killing Curse. Voldemort is disembodied and Harry since then carries a mysterious scar on his forehead as a result.

In the fourth instalment of the series, Harry Potter and the Goblet of Fire, Voldemort appears at the climax of the book. It is revealed that Voldemort's minion Barty Crouch Jr, disguised as Hogwarts professor Mad-Eye Moody, has manipulated the events of the Triwizard Tournament. Voldemort's goal is to teleport reluctant participant Harry Potter to the Little Hangleton graveyard, where the Riddle family are buried. Harry is captured and, after Death Eater Peter Pettigrew uses Harry's blood (which would prove to be a major flaw) to fulfil a gruesome magical ritual, Voldemort regains his body and is restored to his full power. For the first time in the series, Rowling describes his appearance: "tall and skeletally thin", with a face "whiter than a skull, with wide, livid scarlet eyes and a nose that was as flat as a snake’s with slits for nostrils". Rowling writes that his "hands were like large, pale spiders; his long white fingers caressed his own chest, his arms, his face; the red eyes, whose pupils were slits, like a cat's, gleamed still more brightly through the darkness".

In the fifth book, Voldemort makes liberal use of the Ministry of Magic's refusal to believe that he has returned. Voldemort engineers a plot to free the Death Eaters from Azkaban and then embarks on a scheme to retrieve the full record of a prophecy regarding Harry and himself which is stored in the Department of Mysteries. He sends a group of Death Eaters to retrieve the prophecy, where they are met by the Order of the Phoenix. All but one, Bellatrix Lestrange, are captured, and Voldemort engages in a ferocious duel with Dumbledore. Voldemort attempts to possess Harry Potter but finds that he cannot; Harry is too full of that which Voldemort finds detestable: love. Sensing that Dumbledore could win, Voldemort disapparates, but not before the Minister of Magic sees him in person, making his return to life public knowledge.

In the sixth book,Voldemort once again declares war, and begins to rise to power once more. He murders Amelia Bones of the Department of Magical Law Enforcement, and begins to target members of the Order of the Phoenix, including Emmeline Vance. Going into the final book Voldemort furthers his quest for ultimate power. He disposes of the Minister for Magic and replaces him with his own puppet ruler, giving him control of the Wizarding World, persecuted and arrested Muggle-borns for "stealing magic" from the 'pure blood' wizards. After failing to kill Harry with Lucius Malfoy's borrowed wand (to avoid the effect of Priori Incantatem), he goes on a murderous search for the Elder Wand. His journey also takes him to Nurmengard, the prison where Grindelwald is kept. He ends up killing Grindelwald as well. After finally locating it and stealing it from Dumbledore's tomb. He murders Snape believing it would make him the true master of the Elder Wand, since Snape killed Dumbledore. He then calls an hour armistice, in exchange for Harry Potter. When Harry willingly walks into Voldemort's camp in the forest, Voldemort strikes him down with the Elder Wand. However, the use of Harry's blood to resurrect Voldemort's body proves to be a major setback: while Harry's blood runs in Voldemort's veins, Harry cannot be killed. Instead, the part of Voldemort's soul that resides in Harry's body is destroyed by Voldemort himself. Voldemort forces Hagrid to carry the apparently lifeless body of Harry back to the castle as a trophy, the sight of which sparks another battle. Revived, Harry reveals himself and explains to Voldemort that Draco became the true master of the Elder Wand when he disarmed Dumbledore; Harry, in turn, won the wand's allegiance when he took Draco's wand. Refusing to believe this, Voldemort casts the Killing Curse with the Elder Wand while Harry uses a disarming spell with Draco's, but the Elder Wand protects its master and the spell rebounds, killing Voldemort.