Ruby (Omniverse)

Ruby is a demon in the series: Power Rangers: Omniverse

Biography
Ruby was a demon devoted to Lucifer's return. After Azazel's death, she conspired with Lilith as to how they would free Lucifer from his cage: while Lilith broke the seals, Ruby protected the remaining "special child with demonic powers", Kurt Mendoza, and prepared him to break the final seal and to become the vessel of Lucifer. This plan was known only to herself and Lilith, causing Ruby to be regarded as a traitor by Hell during her time with Kurt.

At first, Ruby cared for Kurt when he was being tortured in Hell after sacrificing his life to save Hunter's. She promised to help Kurt get out of Hell and to train him with his special demonic powers to be able to kill Lilith in revenge for being sent to Hell. Through his grief difficulties in his time in Hell, Kurt and Ruby's relationship gradually deepened and eventually became sexual up to the point where they had intercourse while in Hell.

Soon after Kurt was resurrected from Hell, thanks to the angel Castiel. Ruby tightened her hold by being useful and 'helping' Kurt back on Earth, saying what he wanted to hear, addicting him to drinking demon blood, and She molded him into the perfect vessel for Lucifer and manipulated him into breaking the final seal by killing Lilith, but once her deceit was realized by both Hunter and Kurt, she was ultimately killed with her own demon-killing knife that Hunter used against her in the final showdown with Lilith.