Jen

Jen is a Light Spirit, a creature that produces a main component of Life known as "Light". (also vessel's main power source)

Jen is Go-Go's sassy life support machine best friend. 

She has the personality of a 16 year old tomboy. Unlike Go-Go, she loves swearing. 

She was sent to the country of Creatia from "The Light Dimension", to find Go-Go. After like a week, she finds him at the bottom of a hole covered in trash and nearly dead. To save him, she links the two of them via the string. If the string is disconnected, Go-Go has a seizure, heart attack, menstural cycle all in one and starts dying. 

So Jen is now professionally handcuffed to a depressed 14 year old.