Mermaid Heel is known as an all-female guild, with the entirety of its shown members being females. Millianna confirms this when she responds to Erza's question, about if Shô and Wally are in the guild with her. She says "What are you talking about? Mermaid Heel is a guild limited to women." When Hibiki Lates jokingly said that he would have joined Mermaid Heel, Toby Horhorta angrily commented that the Blue Pegasus Mage "is way off their theme".
Location and Building
Mermaid Heel's exact location is unknown. However, its guild building has been shown. The building is identified by a large banner held up by a pole on its side while also having the name of the guild written above its entrance. Mermaid Heel's headquarters itself is made of bricks while having a body of water nearby as well as having multiple water drains on and around the building. Topping the whole structure is a massive statue of a Mermaid with its head facing the front of the building while both of its arms supports its body while raising its tail upwards.
Mermaid Heel appears to be a considerably powerful guild, whose team for X791's Grand Magic Games made it 6th out of eight squads completing the preliminary event "Sky Labyrinth", which had 105 other competing guilds disqualified. Such an achievement is made more notable by the fact that one of the teams they managed to outrun, representing Fairy Tail, the strongest guild in Fiore, and counting strong individuals such as S-Class Mage Erza Scarlet and S-Class candidates Natsu Dragneel, Gray Fullbuster and Elfman Strauss, made it only 8th during the preliminaries, barely gaining a place to take part in the real Games. Most of Mermaid Heel's power and reputation seems to stem from its strongest Mage, Kagura Mikazuchi, who has been described as being on the same level as Erza Scarlet, one of Fairy Tail's S-Class Mages, as well as the guild's most powerful member.
|Legal Magic Guilds||Blue Pegasus • Carbuncle • Dullahan Head • Dwarf Gear • Fairy Tail • Gramlush • Hound Holy • Lamia Scale • Magia Dragon • Mermaid Heel • Mount Altana Guild • Orochi's Fin • Phoenix Grave • Quatro Cerberus • Sabertooth • Scarmiglione • Titan Nose • Twilight Ogre|
|Independent Guilds||Crime Sorcière|
|Other Guilds||Diabolos • Fairy Nail • Edolas Fairy Tail • Love & Lucky • Southern Wolves • Sylph Labyrinth|
|Former Legal Guilds||Cait Shelter • Phantom Lord • Raven Tail • Red Lizard|
|Dark Guilds||Dark Unicorn • Death's Head Caucus • Harpuia • Naked Mummy • Red Hood|
|Former Dark Guilds||Blue Skull • Edolas Fairy Tail • Eisenwald • Ghoul Spirit • Grimoire Heart • Oración Seis • Raven Tail • Reborn Oración Seis • Succubus Eye • Tartaros|