Dion Isaacs (the reincarnation of Dionysius), Athena's brother, is wreaking havoc. After to an unfortunate bee-venom poisoning at his wine business, he is down on his luck and crashing at Athena's place. But the former god of wine, feasting, and excess is a bad influence on Fanny's best friends, with his partying, wacky business schemes, and general debauchery. Sure, Dion is a fun guy. But there is such a thing as too much fun, and Fanny seems to be the only one who sees it.
Meanwhile, Fanny's mother is suffering from hyperemesis gravidarum, which basically means she pukes all the time, because she's pregnant. With her mom unable to work, her dad is taking extra shifts to make more money, and things are getting tense at home. Fanny is excited to be a big sister, but all this sickness and stress over money are starting to take their toll on her.

Can Fanny save her friends from Dion's negative influence, while also solving her family's money problems? Of course she can. She's Fanny Fitzpatrick.