The Rotten Eggs (腐り卵 Kusari Tamago) are a notorious group of delinquent male aristocrats who roam the streets of Lotto Valentino in the early 1700s.
Over the course of the 1690s and early 1700s, Lotto Valentino bears witness to the birth of a small number of criminal bands within its walls, all of which are composed of unemployed young men.
The Rotten Eggs is one such group and considered the worst of the lot, organized by the young aristocrat Aile as a form of rebellion against his parents and the city itself. Unlike typical street delinquent gangs, the Rotten Eggs' members are all aristocrats—most about five or six years younger than Aile—and their vulgar, aggressive activities further contribute to their notoriety: not only do they commit theft and extortion, there are even rumors that they raid merchant ships at night.
Most of the group's notoriety is the fault of the ordinary members of the gang rather than Aile, who never spearheads their various wrongdoings. However, his unparalleled skill with a knife ensures that his position as leader is never contested.
Despite their reputation and criminal standing, the Rotten Eggs do not cause broad long-lasting damage. This, coupled with their aristocratic status, leave the City Police able to do little more than arrest individual members for individual acts.
In the summer of 1705, five Rotten Eggs delinquents accost Niki in the marketplace and attempt to drag her away—only for passerby Monica Campanella and by extension passerby Huey Laforet to intervene. The Rotten Eggs are further undermined when an ox goes on a rampage, giving Elmer C. Albatross the opportunity to lead Niki away from her accosters.
Once the delinquents extract themselves from the chaos, they catch up to Elmer and Niki in the marketplace and ask what happened to the other two interventionists from before. Niki says that they were arrested by the City Police, and the delinquent with the swollen eyes prepares to beat her as punishment for her refusal to sell 'it' (drugs). All the marketgoers ignore him and the other delinquents as he squeezes Niki's throat, leaving Elmer to point out that Niki cannot reply to him if she cannot breathe.
The swollen-eyed delinquent relinquishes Niki in the face of Elmer's unnerving advice, and he and his friends surround Elmer in an attempt to intimidate him. Unintimidated, Elmer offers him advice on his bruised eyes and earns himself a punch for his troubles; undeterred, he declares that the delinquents should smile when they hit someone so he can be sure they are having fun. Considering that the victim is likely to be unhappy, at least someone should be enjoying themselves.
Unnerved, the delinquents prepare to beat Elmer half-dead—but Elmer and Niki are rescued by Denkurō Tōgō and Zank Rowan, two foreign swordsmen who speak in a language (Japanese) neither the delinquents nor anyone else understand. They take out four out of the five delinquents and are subsequently threatened by the swollen-eyed delinquent. Zank, recognizing and dismissing the delinquent's affluent wealth, resigns himself to the possibility that he may have to kill the man; when the delinquent draws a small knife, Zank prepares to draw his own sword.
Aile shoulders his way through the crowd, and his tall height and affluent attire draw all eyes to him. The delinquents cry out their relief, but hem and haw when he asks what they have been doing. Upon looking over at Elmer, Nile, and the bald man, he guesses that they were attempting to buy 'that' (drugs). One of the delinquents, confident now that Aile is here, shouts at the foreigners that "it's over now." Aile agrees, and then stabs the delinquent's own knife into his palm. When the delinquent drops to the ground, Aile steps on his neck.
Once the delinquent loses consciousness, Aile requests that Zank and Denkurō leave matters where they currently stand. Zank reluctantly agrees, at which Aile advises him and his companion to leave the city swiftly. Moments later, the City Police finally arrive on the scene.
In the ensuing weeks, the Rotten Eggs are conspicuously absent from the street.
Aile remains the leader of the Rotten Eggs over the next two years, until he turns over a new leaf in 1707 and begins studying alchemy under Dalton Strauss. Without Aile to lead them, the Rotten Eggs are far less effective and considered inactive by 1710.