fuyero is incorrectly written and should be written as tricky as its meaning: lunfardo Version of tricky. See disloyalty.
The correct term is nightmares. In Colombia it is used as a synonym for false, misleading. scammer, scammer, dishonest, cheat, talkative, gossipmonger, reckless, lenguilargo. We even use a very similar word Fulero, which means showy, flashy.
Person likes to speak of others and invent things about them that are not true