WoWDB

Rooby Roo is a ghostly pug sitting inside the inn of Admiral Taylor's garrison.  Apparently, as you learn from interacting with her, she's hungry and maybe his owner will know what to do.

Go down the staircase nearby and buy 3 x  Rooby Reat from Miril Dumonde.  Return to the pug and feed her a treat by using a rooby reat while targeting her.  Follow her as he moves and give him a treat each time she stops.  After the third treat, she leads you to a pile of... Rooby's Roo.  (I literally banged my head against the computer desk at this point.  Blizzard, please...)

The pile of poo is now active as a container, so right-click it and loot  Rooby Roo's Ruby Rollar.

Treasures have quests that track a character's progress, so you may run the following script to see if you've already looted the necklace:

/run for k, v in pairs({RoobyRoo = 36798}) do print(format("%s: %s", k, IsQuestFlaggedCompleted(v) and "\124cff00ff00Done\124r" or "\124cffff0000Not Done\124r")) end