The question of whether Severus Snape was a Slytherin or not has been a source of debate among Harry Potter fans for years. Upon their arrival at Hogwarts, the Sorting Hat placed Snape and Lily into Slytherin and Gryffindor Houses, respectively. Although Snape was sorted into Slytherin, his behavior and attitude throughout the series suggest that he was not a true Slytherin.
Snape was often seen as a villain in the series, but he was not truly evil. He was often seen as a loner, and he was not very popular with the other Slytherins. He also did not have the ambition and drive that are typically associated with Slytherin House. He was not motivated by power or wealth, but rather by his love for Lily.
Snape also did not share the same values as the other Slytherins. He was not interested in gaining power or manipulating people, but rather in protecting those he cared about. He was willing to risk his own life to protect Harry and Dumbledore, and he even sacrificed himself to save Harry in the end.
Snape was also not afraid to stand up for what he believed in. He was willing to defy Voldemort and the other Death Eaters, even though it meant risking his own life. He was also willing to help Harry, even though it meant going against the wishes of his former master.
In conclusion, it is clear that Snape was not a true Slytherin. He did not share the same values and ambitions as the other Slytherins, and he was willing to risk his own life to protect those he cared about. He was not motivated by power or wealth, but rather by his love for Lily. He was a complex character, and it is clear that he was not a true Slytherin.