Pure Evil Buu Bio
After Buu dispelled the evil from his body, the vapor gained this tall, emaciated form. This Buu represents the dark side of Fat Buu and has the bulk of the original Buu's power, since Buu was originally created through pure evil. This also explains why his reaction to the shooting of Mr. Satan was so despicable, and even appalled the Fat Buu. He is a polar opposite of the "good" Buu in all aspects apart from apparel, including the color of his flesh (a drab grey) and gravelly manner of speech. The two Buus fight, with the evil incarnation gaining the upper hand and consuming "Good Buu" after reflecting an attack meant to turn him into chocolate. By consuming the Good Buu, the Evil Buu transformed into Super Buu.