Blank Man:

A mysterious presence that passes from Joel to Sara, and from Sara to her son. Theories persist that this "Blank Man", as Leif, Sara's son calls him, is one and the same as the Angel Joel and Connor spoke of in The Judas Syndrome.

The Blank Man is named as such because when he appears to leif, he is without features, only form. This same description was confirmed by one of the witches Leif met in his first few weeks of life, and again when Sara first laid eyes on him.

A powerful entity, as revealed during a séance, the Blank Man is thought to be a good spirit, a guide that would resurface time and again in Leif's life.