There was a gleemake of the song "No Air", originally sung by Jordin Sparks and Chris Brown. In the TV show Glee, it is sung by the characters Rachel and Finn.
Person / Persons who are always happy, and tend to not to stray to typical 'emo' trends. In fact, they find the idea quite repulsive. Thus, the emotion that they convey is always glee. Not for use in a derogatory manner.