The Unseelie Court is widely known to be the least noble of the two fairy Courts of Prettania. Aristocracy belongs to the houses with the strongest fairies, those who excel in glamour and magic, and minor houses are born and die every month. The oldest houses still exist because they are powerful; they know that in order to maintain their line, each generation must marry the most powerful scion possible in order to produce strong heirs, and to that end, any means is fair game. Assassinations and maiming, secret duels and plots are common currency in the Unseelie Court.
Even the plebians fight among themselves, so that only the strongest, cleverest, and most powerful survive.
It is not surprising, therefore, that the Thrumli's presence went unnoticed for so long. Had it turned up in the Seelie Court, where every death was either King's order or punishable by the same fate; where nobles disliked to get their hands dirty and commoners didn't dare; where there were laws - had the Thrumli acted there, it would have been discovered at once, and some means found to destroy it.
There were no laws in the Unseelie Court.
In the Inkestwood, the deepest, darkest corner of the Unseelie lands where not even the moonlight reached, the fae had long since lost their eyes for more useful senses, and the hapless few who wandered in with a torch had a short glimpse of something white and blind and ethereal, like those fish of the deepest oceans, before both light and life were abruptly extinguished. There, three moons before Arwyn's return, the mutated descendants of a nixie turned on their mother and ate her alive, before turning on each other.
Further south, if south you could call it, deep under the Silver Mountains, the last peace treaty between goblins and dwarves was torn to shreds along with the goblin tribe massacred by one young dwarf - a mute and a simpleton, who before then had never been known to hurt a fay.
In the Capital, an entire household was found dead, one member in each room of their home. One had banged his head against the wall until he cracked it, another had eaten his own arm, and third had stuck iron pins in his eyes - the question as to where and why he'd gotten such Catspawn objects ran across the grapevine like lightning from cloud to cloud, landing nowhere.
Even in Sundown, a swarm of fey gathered as if to dance and mate, but instead began attacking every other thing in sight, until a boggart swallowed them all and died of it - but the story was eclipsed by Arwyn's return.
It wasn't until a group of exiled Seelie rebels, brothers all of them, like fingers on a glove, turned on each other the moment they were through the barrier into Unseelie lands, to the bewilderment and fear of their Escort, that the matter was brought to the attention of Oberon, and the Seelie King, knowing what it was and knowing it could not pass the barrier into his realm, decided not to inform his rival Queen, but instead let the Thrumli do his dirty work for him.
Which was her plan, of course.
