Rail is a homunculus who was created by Huey Laforet and Salomé Carpenter in their research laboratory 'Rhythm'. The experiments inflicted on Rail when they were a live test subject would eventually rob them of the ability to feel pain, and are the reason they have large stitch-marks scarring their body. Out of all the Lamia members, Rail is by far the most outspoken about his bitter, deep loathing for Huey and the trauma Huey caused.