Although official Church doctrine changed in 1969, for more than 1,000 years and persisting in her folk understanding, Mary Magdalene was associated with Mary of Bethany and the unnamed "sinful woman" who anointed Jesus' feet with her tears, wiped them with her hair and perfumed them.
A cultus developed around her c 700 CE, where she occupied a space "suspended between sacred and profane", "a woman of ambivalent character, torn between her human nature and her desire for the sacred," according to Marcello Mignozzi. As such, she became a figure to be petitioned for all matters - whether profane or sacred - and was revered as leading on a path of achieving the alchemy from the former to the latter.
These cards were produced by a more mainstream Christian printer and contain a more mainstream biography on the back, but the icon is nonetheless totally appropriate for either virtue or vice.
In some traditions, these would be made stronger by doing a covert working with the icon before or after (or while) having it blessed by a priest. In this way, apparently mainstream saints could reinforce blessings and petitions that a priest wouldn't otherwise sanction.