John

John is revealed to be the "spirit" or owner of the Titans bathroom. He is first introduced in Serious Business. He doesn't seem to be either a friend or villain to the Teen Titans. Although Beast Boy did show some familiarity with him, as when John appeared, Beast Boy said "what's up John?", while the other Titans were shocked to see him.

Biography
John says that he comes from "magic". He claims that himself along with his people come from another world that was destroyed long ago, and his species made a new home on Earth. It upsets John how the people of Earth do not appreciate the bathroom, and that he appreciate the planet with nothing in return. John then goes on to say to Robin and the other Titans how they turned a place of magical fun into one of strife. After, John says how he and his kind will leave the world forever, and proceeds to detach the whole bathroom off the Titans Tower. All the other bathrooms in Jump City, and presumably the world disconnect from their homes and follow John to the orbit of space. The gang then watches with awe, as hundreds of bathrooms ascend into the sky. Beast Boy comments where are they going, to which Robin replies "they're going home" with a happy yet sad expression. Starfire corrects Robin by saying John said their home world was destroyed, and Robin simply replied "I don't know" smiling looking off into the sky.

In space, John with the other hundreds of bathrooms join hands, and spin around counter clock-wise at rapid speed. They all then take off at unhuman speeds and disappear into space, where they expectantly find another planet to live on. Raven comments what to do now that they are all gone, and Cyborg agrees saying he has to really use the bathroom. The five teenagers then break into smiles and sing the Pee Pee Dance once more in the once bathroom of Titans Tower.

Trivia

 * His name is pun on the term "The John", which literally means "toilet".