Board Thread:New on BlazBlue Wiki/@comment-28541692-20160813111852/@comment-39581574-20200303165119

Well from what I seen in this wiki and the other as well as in the games along with spin offs...the conclusion is that he is the child of the 5th Boundary Interface Prime Field Device (Who is based on Saya Terumi the little sister of Naoto Kurogane) and A Black Beast or rather the Primordial being that existed within the boundary rather than the one that appeared in the Dark War (Now this Black Beast existed was well before recorded history. Lulled by the Azure Shrine Maiden, it emerged from a cauldron within Wadatsumi, Japan. Before it could harm the world, the Maiden lured it back into the Boundary, sacrificing herself to prevent calamity. This land was later protected by her descendants, the Amanohokosaka Clan, for millennia as this very own Black Beast appeared during the Prime Field War) as this makes Ragna along with Saya and Jin artificial humans.

Then after the whole Terumi issue where he burnt the church down kidnapped Saya where Jin just...vanished and in one timeline Rachel in one timeline (The one where Noel doesn't exist which is Hakumen's timeline) bites Ragna it made him part Vampire but in others he just gets the Azure Grimoire so...my guess you can say he is an artificial human (But also a semi vampire if you count that one timeline).

(Hope that helped in some way?)