Scylla

Scylla is a character exclusive to the Winx Club Comic Series. She makes her first and only appearance in Issue 104: The Mirror of the Sea initially as a sea monster who had been cursed by an ancient witch alongside her beloved, Charybdis.

Sea Monster
As a monster she looks like a humanoid octopus. Her lower body is nothing but tentacles, and she has tentacle like hair. And her body still has a female figure.

Human
As a human she has light skin, pink lips, bright blue eyes, and pale pink hair. She wears sandals and has on a pink toga.

Personality
She is a good and innocent person. Even as a monster she didn't want to attack the Winx she just wanted their help, so she can be turned back to normal. She also cares deeply for Charybdis.

Pre-Comics
Scylla and her fiancé, Charybdis, were set to marry but the jealous Circe (who was in love with her fiancé and rejected by) turned them both into sea monsters. From then on, they roamed the oceans together becoming terrifying mythologies to humans.

Season 5
Scylla comes to the aid of her fiancé when the Winx misunderstood that he had attacked fishermen and now them. She grabbed Bloom's wrist to stop her from using her spell on Charybdis. Phylla demanded Scylla release Bloom at once to which she obliged with no contest. She then goes to check up on Charybdis, to make sure he was alright.

Once Flora noticed that she did not want to harm them, Musa uses her musical flute to read both Scylla and Charybdis's feelings. Scylla informs Musa of her and her fiancé's story on how they became sea monsters. Because of the Fairy of Music's power, Scylla and Charybdis were able to clarify "the assault" against the fishermen and the Winx. The truth is because of Charybdis's massive size, he unintentionally creates vortex whenever he swims but he and Scylla are not evil.

Scylla then receives help from the Winx which she appreciates. She explains through Musa that the only way to return them to their human forms is through the Mirror of the Sea which is located on an island not too far from where they are now. She and Charybdis lead the Winx to the island. The island that was once Circe's former home who was in deep slumber as a statue.

Scylla and Charybdis wait for the fairies to locate the mirror. Once they do, this awakens Circe who try to stop her intruders from taking the mirror. This causes her to step outside in search Bloom and Stella who have the mirror. When Scylla sees Circe, she calls her out which distracts her long enough for Stella to cast her spell and return Scylla and Charybdis back into their human forms, and turning Circe into a small crab.

Scylla is overjoyed that the spell is finally broken and lovely embraces her fiancé after so long. She thanks the Winx for their help.

Trivia

 * Scylla was inspired by Scylla from Greek Mythology, a Naiad (a nymph of freshwater). The Sea God Glaucus loved Scylla, but the Sorceress Goddess Circe loved Glaucus and was jealous of Scylla, and transformed Scylla into a horrible monster out of jealousy. Scylla's monster form had four eyes, six snaky heads, twelve tentacle-like legs, a cat's tail, and six dog heads on her waist which would each eat a crew member from each ship which passed near her. Scylla was believed to live on one side of a channel opposite to another dangerous monster, Charybdis. Charybdis and Scylla were both very dangerous for ships who passed to close to them, and the channel they were located in was so narrow that sailors would be caught by one of them when they tried to avoid the other.
 * The story of Charybdis's and Scylla's channel is the origin of the proverb "Between Scylla and Charybdis", which refers to a situation where one has to choose the lesser between two evils or where one gets caught in a dangerous situation while trying to avoid a similarly dangerous situation.
 * According to the Greek mythological poem, The Odyssey, after leaving the island of the sorceress Circe, the hero Odysseus had to pass through the channel of Scylla and Charybdis and he chose to avoid Charybdis and pass near Scylla since Scylla was less dangerous.