કામદા એકાદશી
Story
A Gandharva named Lalit was cursed to become a demon. His wife Lalita observed this Ekadashi and the merit freed him from the curse. Lord Krishna told Yudhishthira that this Ekadashi fulfils all desires (Kama = desire, Da = giver).
Spiritual Benefit
Fulfils all desires, removes sins equivalent to killing a Brahmana, grants liberation