"Lora" was a supposedly Human female whose appearance was once assumed by a Rigellian hypnoid while the creature was being manipulated by Harcourt Fenton Mudd.
In an effort to convince an audience on the planet Motherlode to buy love potion crystals from him, Harry Mudd was trying to persuade the crowd that having exposed Lora to the crystals had caused her to fall in love with him. Thus, "Lora" spoke affectionately to Mudd, claiming to have been lonely for him and pleading for him to return to his ship with her.
After Spock fired a phaser at the illusory female, the hypnoid resumed its natural, reptilian form, exposing Mudd's deception. (TAS: "Mudd's Passion")
The voice of the hypnoid as the illusory "Lora" was provided by Majel Barrett.
The name "Lora" comes from the final draft script of "Mudd's Passion". Although it is not entirely clear what species the illusory female is meant to represent, the script establishes her as Human. Only minor other details regarding the character's appearance are established in the script, which (besides an introductory description of her as "a Human girl") otherwise refers to her merely as "a stunning beauty" and "the beautiful girl."