During his fourth year, Harry accidentally visits Dumbledore's Pensieve and learns that Snape was once a Death Eater but is now, according to Dumbledore, a spy for the good side, at great personal ...

That leaves a two-year window between Snape's worst memory witnessed by Harry in the Pensieve, and James and Lily getting together. During this time Severus and Lily could have formed a friendship ...

Harry Potter fans have discovered a detail that makes Professor Snape’s story even more tragic. Within the Harry Potter fandom, there may not be a more beloved character than Severus Snape.