Ophiuca

Ophiuca, known as Ophiuchus (オヒュカス) in Japan, is a manipulative FM-ian based on the serpent-tamer constellation, Ophiuchus. Her form is that of a dark purple snake, and has the power to control snakes.

Game story
In the game, because of Luna's involvements with numerous FM-ian incidents, caused her parents to transfer her to a new school. She keeps this painful news away from her friends. At the mall, she observes Geo and Sonia while they attend a jungle exhibit, and tailed them out of jealously. There she has an unexpected run-in with her parents, and the confrontation prompts Ophiuca to appear before her. Ophiuca promises to make Luna's parents pay, and Luna allows Ophiuca to invade her heart, merging them together to create Queen Ophiuca. Queen Ophiuca holds Luna's parents hostage demanding Omega-Xis hand over the Andromeda Key. MegaMan eventually defeats Queen Ophiuca, but she tries to persuade Omega-Xis to hand over the key so they may use its power together. Omega-Xis refuses, and Ophiuca is defeated by Gemini on a whim.

Anime story
In the anime, Luna suspects that MegaMan is unaware of his secret identity. It was because of this weakness that she is targeted by "Ophiuca" during one of Sonia's concerts, taking advantage of Luna's desire to see her hero and her jealousy over Lyra Note, who she believes may be romantically involved with MegaMan. Luna allows Ophiuca to invade her heart, merging the together to create Queen Ophiuca. MegaMan and Harp Note team up and defeat her. Unfortunately, Ophiuca escapes.

Later, Ophiuca takes on the form of W Luna while gathering minus energy to recreate the Andromeda Key. During this time, Ophiuca often bickered with other FM-ians over how to spend money, and she herself also developed a love of shopping. Eventually, Ophiuca is deleted by Gemini Spark in order to fill the Andromeda Key.