A rabbit/chipmunk (whichever you prefer) looking, alienic mutant form of creature which exists deep in the sewers.
This particular gremlin has only been speculated to exist as few records or eyewitnesses are readily available to confirm this ancient myth.
Most eyewitnesses do not live to tell the tale after meeting this particularly horrendous monster.
The majority of the unfortunates who encounter a Yeyeng do not live to tell the tale. It is believed that the Yeyeng consumes its victims by eating them inside out.
The remaining survivors are better off dead, having suffered a tremendous trauma. They are regarded as the mentally retarded people among our society and now reside in various mental institutes.
I don't buy the schmegegge about Morty sleeping with Moira.
His version of the story was pure schmegegge.
The whole schmegegge was made up to get Liz a little bit of attention.
Looking or experiencing something nice after witnessing something horrid like a disgusting gif or a disturbing video. Typically used as eye bleach are nice images of whatever makes the disturbed person happy.