Rakdos

Rakdos was a demon lord that wanted to play with the affairs of humans. While visiting with his cult, he bestowed one of his members and her daughters the powers befitting succubi. He sent the mother to go seduce a wealthy merchant after they newly-made succubi sealed his wife away. They didn't account for their young daughter, Eleanor. While the stepmother treated Eleanor badly, Rakdos was kind fo Eleanor when he visited with the knowledge that she could be useful someday. He gave the succubi the idea to try and seduce the local lord and spread his influence that way.

When he heard about Eleanor getting married to the lord instead of one of the succubi, Rakdos decided to take matters into his own hands. Because he'd interacted positively with Eleanor before, so it was easy to secure an invite to her wedding. He didn't anticipate Eleanor's mother, a gold dragon, coming to the party, but she went outside with the others and was of no consequence to him. The party that helped Eleanor in the past (Quest: Cindereleanor) was invited to the wedding and was in attendence to fight against Rakdos (Quest: One Hell of a Magic Show). They convinced the rest of the guests and the bride and groom that there was going to be a magic show outside, which left them alone with Rakdos himself. It was a long and hard fight, but the party ultimately prevailed and killed Rakdos.