@the "I pity you" Anon, I think it started because when Karkat was explaining how troll romance works, he said that any positive affections were mostly based off of pity. I guess people took it and ran with it?

CG: PITY IS OF COURSE JUST THE TONED DOWN VERSION OF THE CENTRAL EMOTION, HATE.
CG: AND ALL THE NUANCES OF PITY MANIFEST AS VARIOUS OTHER KINDS OF FEELINGS LIKE WHATEVER CHEMICAL REACTIONS TRIGGER MATING FONDESS OR THE MYSTERIOUS FORCES THAT ARE BEHIND MOIRALLEGIANCE.