Nicki Minaj was a famous celebrity that nobody really cared about. She benefited nobody and was a complete waste of space. She was killed in a battle against Gertrude.
Upset that nobody paid her enough attention, Nicki decided she needed to become more beautiful. To do this, she injected herself with a beauty serum, expecting to become the hottest woman around. However, things went wrong and she began to mutate into a disgusting purple monster. She deluded herself into believing she was beautiful and attempted to get as much attention as possible. This annoyed Gertrude, another beauty-obsessed creature that believed it was the most attractive thing around. The two got into a deadly battle that ended after they fell off of a bridge and into a river. They both drowned. She later found Deathrock9, Slimer and Skele-Man McGee in the Under World and tagged along with them on their journey to rescue Zippy. She was allowed to return to Earth with them after they passed the three trials of the Nightmare Men.