Yami is the corrupt twin of Hikari. The darkness to her light, the kind of opposites that scoff at magnetism. He is considered by most to be quite impotent while his sister holds Yahti in a favorable orbit. Niche cults have been known to crop up around his name, but little to no ground has been made by these groups. Yami has never had significant following outside of the Treloss and their iterations. All mythology and history regarding his character paints him as a great betrayer of family. Not just any family either but to a twin sibling. Even those twisted cultists who worship Graskoroth in The Commonwealth of Sunken Servants refute Yami’s legitimacy as a child of Grask thanks to betraying the Kraken as well. None believe he serves a higher calling than his own name and power which is one of the few requirements for most substantial belief systems to latch on to.
This has not diminished Yami’s power however. He contains the singular most investment of any creature ever created by Grask and despite a complete lack of Tethers to any Souls on Attovia he remains a formidable opponent to Hikari who cannot let down her guard for fear of losing the front and subsequently her control over Yahti.