The modern, PR-friendly name for The Tohu is ancient. Frustratingly, it's also deeply mysterious. Whether it's an individual, a negative "force," the devil, or just a really persistent group of monsters is completely unknown. The Tohu has certainly manifested as all these things, and no matter what anyone does, it continually resurfaces. It existed before Notte arrived on the scene, so it's at least 15,000... – not that those folks have any idea their organization had its beginning in anything other than the human mind.