There's still plenty of time for Franca to come to terms with what decision to make. In the meantime, it seems Lumian has made his choice. Thanks for the chapter!
There should be an alternative for Despair ritual, or it could be used against the mirror people. The gathering and Underworld arc should start and apparently bonus chapter will be by next week.
franca will probably advance to demoness of despair either through mirror people or tarot clubs help or after finding out the truth she will go villain mode and do the ritual which is unlikely