His abandonment haunted him all through his life and as he reached the age of 30, he gave in to the voices that tormented him. It was these voices that told him to save others from the neglect he had suffered, by killing them.
As the bodies mounted Sebastian took to cooking his victims and serving them to his fellow monks as meals to hide his crimes. Before long he had convinced himself that if he too ate the meat he would never truly be alone again.
Sebastian met his fate at the hands of a local witch who removed his heart and cursed him to rise from the grave every year in search of it. As the curse predicted, Sebastian is brought back to life once a year, but in a desperate bid to regain his mortality, his appetite for human flesh has also been revived.