The group is comprised of four teenagers and their leader Duke. In a flashback to the group's founding, Royal Highness, Happy Child, Blue Bayou and Sweet Juliet are said to have been born with varying special powers which resulted in their being shunned by other people. Their families also abandoned them by sending them away to a boarding school, where they met and, discovering their commonality, began to plot to blow up the school. As they talked about their plans, they were approached by a mysterious person, known only as "Duke", who convinced them not to waste their lives because they were necessary to the world and important.
Tokyo Mew Mew a La Mode
The Saint Rose Crusaders claim they are seeking to reshape the "boring grownup world" into their own utopia using their "intelligence, philanthropy, and elegance". To do this they use the Predasites that has been left behind by the aliens after the events in Tokyo Mew Mew. The Mew Mews continue to defeat the remaining Infusers and the Saint Rose Crusaders try to capture and kill their new leader, Berry Shirayuki. Berry is saved by other Mews and the returned Mew Zoey, so the Saint Rose Crusaders use subliminal messages and hypnotism to turn the citizens of Tokyo against the Mew Mews, including Berry's best friend, and growing crush, Tasuku Meguro.
Each of the Crusaders features in a single major attack against Mew Berry and/or the other Mew Mews, before fading into the background. Towards the end of the series, Mew Berry is able to break the brainwashing spell cast on the public and Tasuku, Duke admits that the methods the Crusaders used were wrong. They are last seen in the series standing together on the roof of a building, enjoying the warm feelings being spread by Mew Berry.