Trasgus wear red clothes, pointy red hats, long black and grey cloaks, or a tight dark brown dress made of tree leaves and moss. These outfits are culturally important, being the costumes they wore when enslaved. Their enslavement took place in their early years, by the Unseelie Court, and their escape marked their finding the more chaotic Unkindly Court.

Trasgus live in small bands led by the toughest, most ruthless trasnos, called gorretin colorau. These bands seek out houses of other fey or of mortals to bring confusion and frustration to, allowing them the chance to steal food and other valuables. On rare occasions, if they are seen, welcomed, and treated well, they will instead do the chores for the family over night. They will usually mock people, play pranks, and harass workers at their jobs, especially isolated workers like shepherds.

Children amongst the trasgu are raised haphazardly, and only a rare few survive, keeping their numbers low. If they live to be old enough to fight, sneak, and steal, they are brought on raids and taught to bring misfortune and confusion to the lives on their victims. If the band meets with other bands, they trade, fight, fuck, or gossip. Gender is roughly acknowledged, but mostly, everyone is treated the same.

The main focus of trasgu life is survival, but the brutality of their bands means few do. Their small numbers make them mostly ignored. Their customs revolve around revenge for the treatment they received from the unseelie and other fey who mistreated them (they hold long grudges against the Seelie and Kindly Courts as well). They have special mystics called gorra encarnada who specialize in tormenting other fey, and xuan dos camios whose purpose is to keep records of their feuds and mockeries.