GB stands for Genderbent

Siren's calling is sort of a twist of Aquatic Mode

A young boy by the name of Adam (Genderbent Aneesah) has been trapped with his gang (The sea scourges) in an underground cave. He longs to be outside again and feel the fresh air. When him and his friend Angelo (Genderbent Angaharaheart) dig to the surface and see light, they find their escape and inform their leader (Insert name for genderbent Melinoe here, cuz the name Kratos was an awkward idea). The sea scourges build a ship and they're off. The ocean is full of dangers, sharks, pirates and even sea monsters, yet the sea scourges can defeat them all, they've been waiting till the day they will be free to explore. However they were not prepared for...sirens.

Natalie (Genderbent Newton from LittleBigPlanet3), a Childlike playfull Siren...

...and Romona (Genderbent Romeo from Minecraft Story Mode Season 2) a Siren who is facinated by the earth.

Natalie is a light Siren and Romona is a healing Siren.

Romona encounters Adam and wants to see him again, as she would love to befriend a human. However, Adam gives a different reaction and mistakes her for a mermaid until (Genderbent Melinoe) tells him it was a siren. The advantage to this is an urban legend called "The heart of the Ocean" Adam decideds to hear his leader out but then he and Angelo both head out when they're free and meet both Natalie and Romona. I drew rhis in real life.

The top one is Romona and the bottom one is Natalie.