Seeping Corruption

"Light confuses the darkness, but even light is not so convincing." -Lord Camber Sen (House Aknelith, Mashangist)
The fundamental conflict between light and darkness extends beyond one over the other. While light and darkness are fundamentally opposed, darkness cannot become light and light cannot become darkness. But the fall of light into corruption destroys the dichotomy. Corruption, the blight of the world, feeds on living essence. As opposed, darkness simply organizes certain elements associated with death that repulses life. While clerics and paladin are sturdy in their convictions of good and evil, corrupted beings are fundamentally beholden to the origin of their corruption.
Seeping corruption is a spell whereby a charmed individual is connected to the service of a patron. This spell is cast upon a flaging soul. Instead of making death saving throws, the individual must make charisma saving throws. If the target of Seeping Corruption fails three Charisma saving throws, the target is aligned to the creator of the effect. If the creator of the effect dies, the target of the spell still has a corrupted soul, drifting to either neutral evil or chaotic evil with the goal to feed on others. This will be done with the intention to preserve themself as best possible. If the caster of seeping corruption survives, there remains a link between the pair. Thus, the target will fulfill the demands of the patron regardless of the consequences of their own being.
As this spell can only be cast on targets that are already charmed, there is no save against the spell. The target's charisma also is reduced to 6, unless the target is already equal to or less than 6.