The Twins and the Pureblood Sickness

With first year over and done with, and Fred fully healed, the twins start their second year. However, something more sinister than last year lurks in the shadows and purebloods of any house are becoming sick with something no one has seen before. When one twin falls victim, will the other be able to save them? Sequel to The Twins and the Psychopathic Bully. Rating may change.