A well-off person may have a maid or two in his house. Likewise, a truly wealthy person may have half a dozen or so, taking care of his understandably spacious home. And of course, it wouldn't be extraordinary for filthy rich people to have a dozen or two of domestic workers to handle the housework of a really Big Fancy House. It also would be expected for aristocratic/monarchic families with large estates, major hotels, cruise ships and the like to have a ~100-strong domestic worker staff.
Compared to this trope, those guys are pikers.
A Maid Corps is an army of multiple hundreds of servants — sometimes apparently thousands — that typically are either way too many for just handling the domestic chores, or in addition to the "traditional" housekeepers and personal attendants, there are a more or less equal (or even greater) number of "maids" who perform decidedly "non-domestic servant" work, which may run the gamut from qualified medical doctors and nurses, to computer specialists, to scientists and mechanics, to personal bodyguards, and even a private paramilitary force. Bonus points if both variants are combined.
Some of the truly huge Maid Corps may leave one wondering how their employer's finances haven't collapsed yet from attempting to employ so many maids for so many (often high-budget) "responsibilities"; thus, having a Maid Corps usually designates a character as obscenely filthy rich.
Note that while the implementation of the first two traits (numbers and "responsibilities") can be somewhat variable (though at least one of them must be used in some form), unless the plot demands it at a certain point (after which it is often conveniently never brought up again), the third (finances) is a practically universal aspect of the trope; a typical Maid Corps should be a financial and bureaucratic nightmare to manage in Real Life.
- The title group of Hanaukyō Maid Tai, and the Trope Namer (tai means "team, corps") and co-Trope Codifier. It also depicts the gender-flipped version (Ryuuka's menservants).
- Gravion: The staff of Klein Sandman's castle, excluding his Battle Butler, are the co-Trope Codifier. To quote the Meido entry: "Servant maids, Guard maids, commando maids, hacker maids, mechanic maids, and even one member of the central robotics team. Who of course turns out to be a Robot Maid". See for yourselves◊.
- Najica Blitz Tactics: Najica's first mission involves a rich woman who is served by such maid-bodyguards.
- Evangeline from Mahou Sensei Negima! has an army-sized collection of Robot Maids living in her bottle-sized villa. Ayaka Yukihiro has the more "traditional" sort.
- Girls Bravo: Fukuyama's estate is regularly patrolled by an army of gun wielding maids, who're all ex-military. But they're mainly there to cater to his perversion, since he has floor vents installed throughout the mansion to create updrafts whenever he wants to see under their skirts.
- Fireball: Drossel has thousands of robotic servants made by her Posthumous Character father. However, they're all invisible and programmed to stay out of her way, so for God knows how long she wasn't aware they existed. And then Gedächtnis told her about them.
- In Sacred Seven, the Aiba Foundation has a literal army of maids. Not only do they take care of the typical house chores, but they also act as Mission Control, use weapons, and pilot support vehicles and generally act as backup for the main characters during battles.
- The Chinese Emperor in Curse of the Golden Flower has literally squadrons of elegantly attired maids. The opening sequences features them getting up, washing, dressing each other, eating breakfast etc. to the sound of a clapper.
- In the Get Smart movie The Nude Bomb, the villain's plan was to first destroy all fabric in the world and then rule it by becoming the only supplier of clothing. The obvious problem (how to provide such clothing) would be solved with his one expert seamstress and a cloning machine, which he planned to use to build an army of seamstresses. (In fact, the revelation that he had a clothing machine was the key to an important plot point that had puzzled the protagonist through the whole movie.)
- Sun Shang Xiang (as she is known in other works) in Romance of the Three Kingdoms was said to have over a hundred maids at her command the very least, all of them trained to be Action Girls by Sun herself.
- Due to an accident with sending generics into Rebecca, there are thousands of copies of Mrs. Danvers in the Thursday Next series. They're used as an actual army.
- In the Discworld novel I Shall Wear Midnight, Tiffany discovers a different side to the haughty and snobbish Lady Keepsake. Visiting Keepsake Manor with Letitia Keepsake (daughter of Her Ladyship) Tiffany discovers there are many more domestic servants on the staff than the size of the place suggests. Letitia tells her that four out of every five are officially retired, and half the rest are paid to look after the elderly retired staff who are no longer capable. Lady Keepsake, for all her impatience, bluster and general horribleness, believes it is only right to look after those in old age who spent their working lives looking after her family. Keeping them in expenses-paid grace and favour accommodation is a pension for them.
- Warhammer 40,000: The Adepta Sororitas have the Ordo Famulus, who work as servants in the households of imperial nobility. While, when seen per household, they are not a corps it is one giant army of maids of the Ecclesiarchy spread thorughout the Imperium and is working as such. They do perform regular maid-duties like educating the children and organising the household with the regular staff, but do so with a greater agenda in mind: They influence both the nobles and their heirs towards the Ordos goals. In a more discret manner they are also spies: They look for any heresy in the nobles household. They also manipulate noble weddings and family ties to both discourage any mutation or taint in the noble bloodline while trying to breed the perfect qualities in the nobles offspring. Finally, they are a literal army, as they all have basic military training and some are veterans of the Ordo Militant of the Adepta Sororitas.
- Touhou: Remilia Scarlet has several hundred maids and is always hiring for new ones. This seems to be mostly for the sake of showing off her wealth or having someone to boss around, as with the exception of Sakuya they're all fairies, who are next to useless for actual work. In one of the official manga she adds a gaggle of hobgoblins to the household roster, who are more competent but mostly kept out of sight.
- Mega Man Battle Network: Yaito has a veritable army of maids, who in the Animated Adaptation can be seen in montages throughout several episodes doing random chores across the city.
- Judging by the number of mooks in maid outfits throwing kitchen knives that show up when everyone in Valestine Castle that wasn't a named character got turned into a monster, Count MacGuire of Ys: The Oath in Felghana had one of these.
- In several of the Castlevania games, Dracula has one of these - the Persephone monsters, who are cute girls in maid outfits, often with vacuum cleaners. They also know kung-fu.
- Kesselring, the transgender vampire gentleman from the Rance series, has a whole army of maids, both ninja and otherwise, under his command. It is comprised entirely of battered women that he took under his care.
- The Royal Navy is Azur Lane has the Royal Maids, led by Belfast, and made up of the Town-class cruisers (minus Southhampton), the C-class cruisersnote , the Kent-subclass of the County-class cruisers, and Sirius of the Dido-class cruisers. As they are all Anthropomorphic Personifications of British warships from World War II, all of them also count as ninja maids, with the Royal Maids being just as much a Praetorian Guard as they are maids. Sirius is even stated to have been brought on specifically to perform bodyguard duties, and is extremely bad when it comes to doing anything a normal maid would do, while Sheffield is in expert in cleaning up "garbage" and "messes" with her pistols (Thanks to her detergent bullets, she's also good at cleaning up garbage and messes with her pistols)