Rose poses as an intern to the mayor of Rococo. In reality, however, she is an executive of the evil "Hackers" organization.
She uses the mayor in order to obtain the Tetron shards, which when recombined, gives one power over time. Eventually, she ends up replacing the mayor with an impostor. Once found out, she retreats to the Hackers headquarters and works with fellow member Blackmore, who (upon defeat) ends up destroying the building in a rage and sending the hero and Rose 100 years into the past. Here, Rose decides to eliminate the hero herself, using her tank "De Rose". After the battle, she attempts to flee, but falls into the same dark pit that she trapped the hero in. She is last seen in the ending credits, plotting something with Blackmore, the false mayor and a rotten scientist named Dr. Einst (Pepper in the Japanese version). However, their scheme fails and they are run out of town being chased by chickens.