Originated from the 70's superhero cartoon Spaceghost where a space monkey character named Gleek from the planet Exxor would often spit from under his tongue. The word 'gleeking' was derived from this action.
"Nice going, Gleek. I didn't think anything could stop Super-mouth! Your gleeking has once again saved the universe!"
The eventual result of wathcing too muchGlee where the person now believes that all the songs redone on the show are now much better thatn the original