[Severus (Snape) – Sever means “to cut off.” Snape appears to have “cut off” his ties with the Dark Lord through the first five books and then with Dumbledore and the Order in Half-Blood Prince. “Severe” means “cruel, strict” – two characteristics that accurately describe the Potions professor. ] - Harry Potter Wicka
This image of the dark character with the harsh name is what created readers and audiences alike to distance themselves from the idea that the characters ability to become savior-like, impossible
Severus lead a life of a " half blood" wizard as his mother was of the magical decent and his father was a "muggle", or a human. An unusual character, combined with the half-blood issue, growing up was not easy for Snape. One of this close childhood friends was Harry Potter's mother. Once she met and then married Harry's father, they were no longer close, as Snape was teased by her lover, as a child.
Sparked with interest in dark magic caused Snape to side with the dark lords of the magic realm, which lead others opinion about Snape astray.
After Severus learns of Harry's mother's death, he choses to return to Hogwarts and plays two roles on both sides of good and bad, pretending to stay loyal to the dark society. Although this is apparent, Severus' true desire is only for the good of everyone at Hogwarts school. Severus becomes headmaster at the school.
Severus is forced out of his position as headmaster because of acquisitions leading everyone to believe that Snape was still in alliance with the dark lords of the magic world.
Once he returns,remains and images of the dark lords are still apparent.
** Spoiler** Severus remains loyal to the protection of other, right up until his death. When Snape discovers that Voldemort will kill Harry Potter for the wand, Snape attempts to become the owner of the wand, in order to protect Potter from death. In doing so, Severus Snape sacrifices his own life, and dies.