Kris Mu, also spelled Crys Mu, is one of two fairies featured in the OVA Mutant Turtles: Chōjin Densetsu Hen.
Chōjin Densetsu Hen
Kris Mu appears in the three-volume Super Turtles manga published by Dengeki Comics in 1995. Mu resides in the holy temple of the Neutrino Kingdom where the Light and Dark Mutastones are kept. She instructs the turtles in how the Mutastones work. After the temple is destroyed, she continues to aid the turtles in their ongoing battles against the Shredder, Dark Mu, and the Dark Mutastones.