Kirki was a powerful witch who "chained" her victims with magic herbs and drinks. She lived on the island Ea and was connected with Odysseus and his 10-year effort to return to Ithaca. After the adventure with the Laestrygonians, Odysseus and his crew arrived on the island of Kirki.
A group led by Evrylochos began to explore the island. Arriving at the palace of Kirki, she welcomed them offering them a hearty meal. Evrylochos did not pass the gate of the palace. He remained outside in order to observe and intervene in case something happened to his comrades in the palace.
Indeed, the terrible witch had imbued the food with magic herbs. All the messmates were transformed into pigs. Facing the terrible fact, Evrylochos ran back to the ship and Odysseus.
Odysseus, with the help of Hermes who offers to him the antidote to the spell of Kirki, goes to the palace. When she sees him she instantly falls in love with him and wants to keep him on the island. She knew, however, that this could not happen.
So, she decided to help him. With her amazing skills, she showed him the shortest way for the return to his homeland.