In history, Janissaries were the slave-soldiers of the Ottoman Empire, and the personal army of the Caliph. Not-quite slaves, and not-quite free, they were, for nearly 500 years, some of the most feared soldiers in the Western world.
In Malaster, the idea of a slave-soldier is far from unknown. Although few nations field very large armies, many have need of soldiers that are loyal - that can only be loyal* - to the local potentate. While some trust in the allure of gold - and the threat of a bad reputation - to keep mercenaries in line, and others try and develop familial bloodlines where (hopefully) blood will run thicker than water, some more pragmatic (if less, strictly speaking, good in alignment), have developed janissary regiments of one sort or another.
Many species can end up in these units - although, typically, nations which use them tend to have favored targets of oppression. Goblinoid units are somewhat common in the Northlands, while southern nations often prey upon humans of differing countries and/or religious beliefs. Elves see little if any use in such units - only magic can keep an Elf who does not want to be imprisoned or enslaved alive for long (although many elves will not choose to discorporate because of simple - or even not-so-simple - slavery - preferring instead to simply outlive their master - eternal servitude in a military unit that could take centuries to finally be disbanded is another matter), and halflings and gnomes are rarely used for reasons that might be obvious.
Curiously, Dwarves are more often the instigators of such units than they are victims. While Dwarven infantry is famed throughout history as powerful shock and siege troops, none can claim they are horribly mobile - even Dwarven reconnaissance forces, while cunning and silent, are far from speedy. As a result, some Dwarven nations create janissary units to shore up their weaknesses on the battlefield - cavalry, archers and skirmishers make up the bulk of these units.
*at least theoretically....
Or, more simply, who the heck keeps these drafty dungeons clean?
Well, in large part, nobody. Abandoned dungeons, tombs, mining complexes, underground fortresses, cavern systems, and the like, are usually far from anywhere someone with a dust allergy - or even a mild case of mysophobia - should be spending any time in. Dust and detritus accumulates - especially in those areas which see some level of traffic from outside. (An exception to this would be some tombs, etc. that lack generally mobile guardians, and are sealed from external intrusion, which can be remarkably dust-free). Areas with frequent external access (whether by adventurers, creatures, or simply animals seeking shelter, etc.) can become positively filthy.
There are some things that can ameliorate this, however. Gelatinous Cubes - long believed to have been deliberately created for this very purpose - scour passageways clear of any organic material, and deposit metallic and mineral gloamings wherever they see fit - often in the corners of turns, for some reason. There are spells (similar in nature to the 6th level spell Guards and Wards) which can banish dirt, grime, and such from whole sections of a complex, while lesser spells and cantrips can be used to clear individual rooms. And there are always effects like permanent Unseen Servants, which can be used to create a perpetual - and invisible - cleaning team.
No, not this Jubilee, more like this one. The Jubilee is a celebration held every ten years, to offset precession, in the most commonly used calendar system on Malaster and Isderay. During this celebration feasts and parties are held, gifts are given between friends, special alms are given to the poor, and there is a general forgiving of debts of all sorts.
In Isderay, the Crown can be asked to intercede in any debt or bond, frequently resulting in the manumission of slaves, the freeing of Crown prisoners, and the nullifying of various debts, oaths, and promises. This forgiveness is also held to be... well, a mitzvah, essentially - by those of lesser stature than the royal houses of Isderay - so while only the Crown may be formally petitioned in these matters, many who hold slaves or tickets of debt choose to release them during Jubilee.
In Malaster, while many differing customs have arisen, and the forgiving of debts and releasing of slaves/prisoners is less common, it is by no means unknown, and many cultures do practice some form of pardon - formal or otherwise - during Jubilee.
Strangely, even some evil cultures also practice some sort of similar behavior - although the granting of mercies and indulgences may take their own forms (swift executions, banishment, etc.) they are - in their own fashion - mercies of a sort.