WilyKit is the female of the Wily's. Her twin brother is WilyKat. Kit and Kat were born to a humble farmer and his wife, and became older siblings to a second pair of twins. It was from their father they learned of the the city of treasures, El-Dara, from his book. One day shattered their lives - When their father was harvesting and took a break to picnic with his family, a twister was fast approaching. Kit and Kat's mother and their little brother and sister made it to the shelter, but a large tree barred Kit, Kat, and their father. He got them over and told them to keep running and not look back. They made it in time to watch as the twister swept their father away to his death.
Without her husband to do the harvest, Kit and Kat's mother had to do it herself, and could barely prepare enough food for all four of her hungry children, and not enough for herself. Kat soon convinced Kit they should leave and find the lost city of El-Dara so their mother could feed their little brother and sister and herself.
They ran away to Thundera, hoping to find information of their goal. Instead, they found only deaf ears to their pleas for spare change and food. They bumped into a man who dropped his coinpurse, and Kat considered stealing it but Kit convinced him to return it. However, when they tried to, the man immediately accused them of being thieves, forcing them to run and hide. Desperate, they eventually decided they'd have to do whatever it takes, and began stealing to survive.
WilyKit possesed the power to hypnotize many beings with her flupe. She would usually play the lullaby their mother used to play to them. WilyKit can be heard playing this song on many occasions.
WilyKit and her brother often wandered the streets, using her flupe to distract and hypnotize civilians while Wilykat steals food and money from them. Upon the destruction of Thundera, she and her brother teamed up with Lion-O, Tygra and Cheetara claiming that they're not following them, the three just happen to be walking in front of them.
When the ThunderCats found themselves at the mysterious Elephant village, WilyKit and the elephant Aburnfound common ground, and through the lullaby her mother sang to her when they were young, WilyKit discovered her flupe can do more than just play music. After Lion-O defeats the wraiths, an even greater threat, a Stone Giant starts attacking the village. WilyKit and the Elephants defeat the stone giant with their musical harmony.
Though not technically a weapon, WilyKit possesses a circular, flute-like instrument called a flupe that seems to enthrall the listener with its melody, holding them in a dazed state. The song that she plays on the flupe in many episodes is actually a lullaby that WilyKat and Kit's mother used to hum to them. The flupe also has destructive abilites when in synch with the Elephants' trumpeting in shattering rock.
Her other possessions are a hoverboard and the Forever Bag, the latter she shares with Wilykat.