Create a pixel art image of a mystical creature that are a fusion of angelic and devilish qualities. The creature possesses features of a Caucasian mature woman. Maintain the low-resolution chiptune art style reminiscent of NES/Famicom games, holding onto the linear typicality of the genre. The creature should be portrayed in a full-body posture against a white backdrop, ensuring that the character's shape is clearly visible and conforms to a seven-head height ratio, a reference to the proportional guidelines used in classical video game designs.