The girlgoyle is the profoundly ugly chick that hangs around with the really hot girl that you are trying to hit on. In order for a successful coming-on attempt, the girlgoyle must be neutralized. This is where one of your buddies must "take one for the team" and goflirt with the girlgoyle, leaving the hot girl available for flirting purposes.
A hiss girl/guy is that one person in primary/high school who was incredibly socially inept and usually squealed or hissed at people they didn’t like thinking it was somehow intimidating, they tended to think they were an anime character/animal of some kind. Hiss girls and hiss guys usually have awe inspiring levels of autism and the most punchable faces on planet earth.
-“Dude what is her problem? Did she just howl at you?”
-“Yeah she’s ahiss girl/guy”