Samahain carries within him darkness that masks a deep and unfathomable pain from his past. It lead him to find release in the darkness, where he found himself enthralled by an Archfey whose offer of salvation cost him more than he could realize. It cost him his name, his memories, and even his mortal soul. Now a Dhampir who's haunted by nightmares, and feeds on the joyful dreams of those who have happiness and love in their hearts.
Samahain betrayed the Silver Stars during the events of 5. Six and made a pact with Byvv before stealing Gwynne Pogodi to replace his own empty soul.