Archive of Our Own

This is a master-post/list of my worldbuilding for my BNHA Little-verse fics as some have reached out and said they felt it’d be helpful for them to have it! I have it marked ‘complete’ for now, but I will add to it when needed :).

WHAT IS LITTLE-VERSE?

Littleverse is an Alternate Universe based on Non-Sexual Age Play and some light BDSM themes having a biological functioning in the “real world.” There are three major classifications for Littleverse that one can be – a Little, Caregiver, or a Neutral/Switch. For my Aus, I also add in scents, pheromones, and a bit more of Omegaverse instincts at play to make it fun.

CLASSIFICATIONS*

* Some AUs, this may be called a “dynamic.” Also, please note that any hormone, pheromone name, etc., is not real and has been created via a name generator.

Little Class

On blood test, this class has the highest production of the hormones lystrin and sutocin (“headspace hormones”), and flotrane (“baby smell pheromone”), and a decrease in trulphine production. 

• Tot (0-2)*

• Rarest of the Little class, >4% 

• Tyke (3-6)*

• Second most common range, ~30%

• Middle (7-11)

• Majority of Littles fall in this range, ~49%

• Tweener (12-16)

• third most common, ~17%

* may need to use supplementary materials in headspace (i.e: diapers, pull-ups, bottles, etc)

Caregiver Class

On blood test, this class has the highest production of the hormones novadrocin and atulcin (“parental hormones”), as well as pholpein (“caregiver pheromone”). They also have moderate levels of trulphine and oxytocin. 

• Babysitter (less intense instincts as a Guardian, often called ‘Big Brother/Sister/Sibling’; often temporary caretakers of Littles) 

• 22% of Caregivers 

• Guardian (preferred and main caretaker of the Little class)

• 78% of Caregivers are Guardians

Neutral Class

On blood test, this class has a normal range of production of Class-specific hormones. Neutral and Switches have higher levels of phytostrin in pheromone production. Switches may have more of an imbalance with Little-specific or Caregiver-specific hormones, depending on where they lean on the spectrum. Baseline have moderate to low levels of these hormones. 

• Neutral (someone who is not classified as the above once tested) 

• 39%

• Switch (someone who has a fluid mindset, and can flip into a Little-space, Caregiver-space, or Neutral-space)

• 21% 

• Baseline (someone unclassified before testing)

• Percentage fluctuates based on population, suspected ~30%

AU MECHANICS

The Department of Classification has three sub departments: Little Welfare & Protection, Caregiver Aid & Security, and Neutral Assistance & Safety. The Department has become an integral part of society ever since more research and knowledge about Classifications and Quirks have developed. In some AUs, the Department may even have much political power in their hands.

Fostering is when Little Welfare has taken custody of a Little in an environment deemed unsafe, negligent, unhealthy, and/or abusive. It has garnered some controversy, especially if the Little in question is of age (physically). A Little can petition to be fostered at any point in their life, and may voluntarily give up custodial rights of themselves until they are deemed healthy enough to make consensual choices. Agents in this subdivision of Little Welfare are called Wardens, though slang for this label is watchdog, minder, and/or watcher.

Adoption happens underground and “beneath people’s noses”. It involves the ‘adoption’ of a Little to Caregiver(s). Many upper-class families do participate in this on the downlow, more so if a Little is from a family of Neutrals and they feel it’s “for the best”. Similar to Quirk Marriages, it is illegal and socially taboo to be known to participate in this. It is also not discussed in “polite society”. A Little’s Quirk may be an important factor in the adoption, along with their vulnerabilities (ie: foster care, mental health, etc). It’s also a common threat in some foster families to the Littles, if they don’t “behave.” Think of child trafficking rings, tbh. 

PROTECTION LAWS

A controversial set of bylaws introduced by the Department of Little Welfare and Protection. Essentially, it describes and outlines the concept of “Conservatorship of Littles,” wherein the Department can declare a Little incapacitated under certain circumstances or if they meet a specific criterion of needs/symptoms. 

Controversy exists in that Littles diagnosed with Classification Rejection Syndrome are automatically considered incapacitated by law, and therefore are legally assigned a Caregiver by the Department. Said Caregiver will be carefully selected based on the Little’s needs, and go through a variety of background checks, financial checks, and the like. Known as the “Caretaker Clause.”

Some criteria are at least two of the following: 

• Little must be diagnosed with Classification Rejection Syndrome (CRS).
• Little must experience symptoms of headspace neglect, scent sickness, and/or other diagnosed mental health issues.
• Little must currently have inhabitable living conditions. Said conditions may be an unsafe environment, unhealthy environment, abusive environment, negligent environment, homelessness, etc.
• A Little’s Caregiver has shown incompetency in the care of the Little.

The Department technically has this system, based on Fostering, but the bylaws allow for greater freedom. However, of the rise in illicit suppressor drugs, and trauma imprinting, public opinion is changing on the protection laws to be more favorable. 

How does one Classify?

It depends on the AU. For some, I have it be a natural “presentation” – similar to how one can present as an alpha or beta in Omegaverse. In other AUs, I have there be a series of tests on what I call a “Presentation Day,” which can either take place prior to high school or during high school.

Presentation Day:

At some point in ones’ life, they are required to take the classification exam—a series of tests, lasting three days, meant to determine their classification. It consists of a medical exam (consisting of bloodwork, typical check-up that includes weight and muscle mass as Little’s have a more lighter, hollowly-ish bone structure, a written exam, similar to a personality test w/ some actual peer-reviewed and reliable assessments, an interview with a Caregiver child psychologist and two social workers from the DoC,  and a practical inside a playroom, playground, or nursery, where they are observed by workers and instructed to act as natural as possible. 

Often, during the bloodwork, there is a specific patch test swiped over ones’ scent glands that behave as an acting agent for the Classification pheromones to “awaken.” In some AUs, there may be something injected into the bloodstream to activate the other hormones (harmless to the rest of the system, of course).

Results are mailed about four or so weeks after the exams have taken place, though one can fully present into their Classification at anytime during “Presentation Day.”

While it is not required, it is highly encouraged for everyone to inform their schools of their classification once they are aware, more so for the Little class than for the other dynamics. Some programs* do require students to inform the school immediately. 

*U.A High School and Shiketsu High require students in the hero program and support course to update their classification forms upon getting results. 

**Contrary to belief, it is impossible to successfully forge U.A. Classification Forms as they cross-check with the Department of Classification. Any attempts will cause an impromptu home visit, an interview with CPS and DoC, and/or a meeting with the students’ homeroom teacher or psychologist on staff to assess risk.

On average, at least 4 first years attempt to forge results. 

Can someone be misclassified?

It is possible to petition the Department of Classification for a retake, but requests are seldom accepted (a home visit does take place, however). It is rare for an exam classification to change. Only 3 changes were recorded, and it was due to trauma and/or severe exam interference. Some who are classified as Little, that have preconceptions about it or other things going on, petition the DoC for a retest.

What are Contracts and why are they important?

Much like in IRL BDSM scenes, contracts list out everyone’s comfort levels, the hard no’s, and is overall just a way to make sure everyone is on the same page at all times. In my AUs, I have contracts act as that conversation piece, but also act as legal protection for all parties involved in case something goes seriously wrong.

Contracts between Littles and Caregivers are processed through a subdivision in the LW&P. Those in the Neutral Class may have a contract with a Little, but it’s mostly in triad or poly situation, more so if the Neutral in question is more on the Little spectrum.

Contracts vary, but all should follow a loose structure of ‘demographics, expectations/rules, and punishments’. It is legally, socially, and ethically required for a Caregiver and Little to have a contract between them, regardless of subclass, especially if the Caregiver is the main caretaker of the Little.

If there is no contract on file, the CG is not legally considered the Little’s CG, and will be restricted in some cases (ie: can’t discharge Little from hospital, can’t visit if not ‘family’ etc). Nurseries are required to have a contract with the Littles on file. It is not required for Daycares, but most have loose contracts as a just in case measure. 

What is a Nursery and Daycare?

It functions similarly to nurseries and daycare centers for IRL kiddos, expect these are for Little’s only. Nurseries also function as a boarding home for Little’s who may be experiencing homelessness, domestic violence, and other issues. There are some laws that have it so that if a Little is in a boarding Nursery for 72 hrs, then custody revokes to the Nursery—unless the Caregiver(s) reached out and it was, for example, a temporary boarding (e.g., CG leaving overseas for a business trip, etc.)

Daycares are the same except they don’t have boarding, and have regular hours. There are daycares that only function during the day, and ones that function during the night, or 24-7 with rotating staff, so it just depends on what’s around you.

Littles can choose to live in a Nursery as well. There is a controversial bylaw that states that if a Little is homeless, custodial rights automatically revert to a Nursery. Another controversial bylaw is that any underage Little living in a nursery is considered a ward of LW&P. 

How does one get into a Little-Caregiver bond?

Courtship does not have to take place before a contract is formed, but is expected on a social level, and is often called “play dating” (Note: think platonic dating LOL). A CG may court their Little by buying them items (ie: pacifiers, stuffies, etc), or taking them out on ‘playdates,’ or having them sleep over in staggered days to become accustomed to the environment. For the Little, they may gift their CG with crafts they’ve made, be vulnerable with them, and so on. Courtship ends once a Little accepts the offer from a CG; no set time limit, but socially acceptable to court for more than four months before having a contract unless in extreme circumstances (ie: if Little shows negative health consequences if left without a CG throughout the beginning of the courtship). 

• ADDENDUM: Dependent on Little’s physical age, mental health state, emotional state, and environment, a Caregiver may have ‘custody’ over them. Some prefectures or countries may even have a CG have complete or partial custody over a Little, regardless of their physical age, as Littles may be seen more as their headspace age than physical. 

In some AUs, the carebond between a CG and Little has a physical and emotional manifestation.

Tell me about headspace!

Truthfully, headspace varies for everyone as it’s such a personal and vulnerable experience, but basically, it’s just safe mental regression, and Little’s often describe their headspace as a “warm, safe space” where they can just float and exist. It’s common for a Little to not be aware of what they do in headspace, and even refer to themselves as split (e.g., “big me” “little me” etc).

Headspace can also be something very fluid and less-defined for a Little, in which they find themselves in headspace often. In that case, depending on how young their headspace is, and if they're able to care for themselves, plus other factors, they may/may not be declared legally ineligible to live alone and must have a Caregiver. 

Are there any -verse specific illnesses?

Most Littles are content with their headspace, but tots and tykes tend to resist the most. Resistance can be seen through the use of suppressors (headspace and scent blockers), deliberate headspace neglect, and ignoring everything about the Little class. Depending on the severity of neglect or resistance symptoms, a Little may be diagnosed with Classification Rejection Syndrome. A Little-leaning Switch may be diagnosed with this as well if they fit the diagnostic criteria. It is rare for a Neutral or Caregiver Class to be diagnosed with CRS.

Some other diagnoses are:

• Headspace Resistance Disorder --- typically when there’s a trauma history with the Little, and they accept everything about their Class except for their headspace as they do not feel safe to Drop.
• Scent Sickness

Feral Response Disorder

People can be feral as a response to trauma, extreme chemical imbalances, or extreme stress. Headspace neglect or resistance in Littles can also cause a feral response. There are four phases, and each can be discovered by a blood test (testing the levels of trulphine), and physical changes of appearance. 

• Phase 1: Eye color is gold, but pupil is normal. Teeth become pointed, almost fang-like. Scent becomes more acrid, but can still be passed off as normal. 
• Phase 2: Eye color is gold-purple, though can be gold-red in some cases. Some teeth have become fangs, and nails may sharpen to a claw-like consistency. Scent has a burnt scent. 
• Phase 3: Eye, including pupil, is black. Fangs and claws. Natural scent is acrid and burnt, almost overwhelming. 
• Phase 4: entire eye (sclera included) is black, no white can be seen; severe health complications can happen if left in this state for long periods of time. can become nonverbal in this state. 
• Notes: Littles may find feral Caregiver’s scents comforting and protective. It is possible to imprint in a feral state. 

Treatments

• A doctor may prescribe aggrelin, humunitor, or Propramicin Alduratant for a feral state along with an intensive therapeutic treatment plan. In severe cases, an inpatient program may be required for resocialization and rehabilitation. For insurance purposes, one must be diagnosed with Feral Response Disorder. 

All About Scents:

An integral part of the Classes involve scent/pheromones. Scenting family members, scent-marking belongings, can foster a healthy balance of emotions and decrease any risk of chemical imbalances. Littles, in particular, need to scent and be scented by others in their family group as it fosters healthy development. There are also slight A/B/O elements such as purring, growling, and nesting behaviors. Growling is only possible in a feral state. 

• It is possible to be diagnosed with Scent Sickness. It happens when someone does not have familial bonds or peer bonds, and essentially only has their own scent on them. Symptoms include: extreme sensitivity to changes in scent, rashes on scent glands, nose irritation, nose blindness, sensitivity to scenting. 
• In extreme cases, Scent Sickness may also cause a person to scratch at scent glands until it bleeds or take attempts to have scent glands removed. In Littles, it is imperative for them to have mittens on to decrease risk of self harm. 

Imprinting is a natural response to trauma, and can happen to any Class. For Littles, imprinting is considered a survival response when in unsafe environments, and can be formed when faced with a Caregiver they trust. Some Littles are capable of sensing their imprint bonds, some aren’t, but a Caregiver will typically not know if a Little has imprinted on them unless they are in a feral state or are told of the bond. Imprinting is also considered a sign of pre-feral behaviors and state. 

What is Little Care?

If a medical professional wants to become specialized in Little care, they must go through a program accredited by the Little Welfare Educational Council of the DoC. Some specializations include headspace neglect treatment, classification resistance treatment and diagnosis, or other typical medical things (ie: illness diagnosis intake etc). When dealing with headspace neglect or resistance, a professional might suggest the use of mittens and ‘babying’ techniques (ie: baby talk, only having formula with melas, being hand-fed, etc) to help a Little grow used to accepting help from a Caregiver and their headspace. 

Caregivers tend to go into child-care/medical/social oriented professions as it soothes their nurturing instincts. Most Pro Heroes tend to be CGs, CG-leaning Switches, or Neutrals. Little Pro Heroes have increased over the years, but sometimes aren’t taken seriously unless they are on a team with a CG*. 

* See Bubble Girl from Sir Nighteye’s Agency, the Space Hero: Thirteen, the Smile Hero: Ms. Joke, Sirius from Oki Mariner Crew, and others. 

There are Class-specific courses (core and elective) one must take once their classification forms are updated/they have presented. In UA, a core class everyone must take in their second semester of their first year is a Mental Health Awareness/Advocacy course and included in the syllabus is drug use/addiction awareness, disability awareness education, and more.  

Core Courses

• Mental Health Awareness/Advocacy 1, 2, & 3*

• Taken every fall semester 

• Discusses drug use/addiction awareness, disability awareness education, and more

• Contracts and Courtship*
• Intro to Little Classification 
• Intro to Caregiver Classification
• Intro to Neutral Classification

* Classes intermingle with each other. 

Most high schools have a section in their school for an internal daycare for Little and Little-leaning Switch Students. Universities and colleges are required to have at least two daycares on campus if student numbers exceed ~4k students. In U.A. High, Caregiver students are required to have a certain number of hours volunteering* at the daycare/nursery as part of graduation requirements. Littles are not required to spend an amount of time in the daycare (save their Intro to Little Classification course), but it is expected they visit at least one a semester. However, if a Little is a Ward of UA then they are required to at least spend an hour per week in the daycare (unless negotiated otherwise).

* If a CG student wishes to be certified in Little Care, they must apply for the certification program course (application dropped off at Recovery Girl’s office), and once accepted, must have 200 volunteer hours at U.A.’s Daycare or an approved outside daycare or nursery.

What about Discipline?

Discipline Rooms are also near the daycare/nursery and are meant to be used in the event of a student needing to be disciplined. Regardless of Class, every student is subject to discipline if they are caught rule-breaking, though not every incident requires a visit to a DR. Every student has a safe word (must be written on the form). Before use, a form must be filled out outlining the reasons and the punishment chosen. Students are not allowed to use the DR on other students. Certain circumstances can be made to have this be otherwise, though only if a teacher is there to supervise.

• ADDENDUM: U.A. has a contract on file with Little Class students. It outlines expectations and rules for the student (as both a U.A. student and personal ones), disciplinarian preferences (ie: if a Little student prefers to be disciplined by their homeroom teacher), and level of comfortability of common discipline measures.

AU-Specific Medications/Drugs*

Scientific Name - Street/Common Name - Purpose 

* medication/drug/chemical names are all made up and used from fantasy name generator

Suppressors are a controversial topic, regardless of legality. Although suppressors are legal and can be purchased either over the counter or prescribed by a medical care professional, many consider the use of suppressors as a sign/red flag of something wrong, and thus are severely stigmatized. U.A. uniforms have a built-in pheromone suppressor. It suppresses some of ones’ scents, but fails during heightened emotions/stress levels as a safety measure. It is so that students are treated on ‘the same level’ and cannot be discriminated against because of their Class. However, it makes it difficult for U.A. to determine if a student is using pheromone suppressors.*

*Students are required to inform schools if they are on suppressors or any health medication.

Pro Heroes tend to use suppressors when on patrol or a mission to decrease any risks. Little Pro Heroes gather the most controversy on the subject due to their Class, however. 

Little Specific 

Headspace Suppressor*

* inhibits the natural production of lystrin and sutocin, main hormones produced when a Little engages in headspace. 

• Subtrim - Void - used as a headspace blocker for Middles and Tweeners. Switches often use this as well. Meant to be digested every 6 hours. Can cause calcium backup and liver failure from overuse. 
• Agebinol - Sugar - used as a headspace blocker for tots and tykes. Meant to be digested every 3 hours; using more than 6 a day can cause medical complications and severe reactions. 

Scent/Pheromone Suppressor*

* inhibits pholpein, phytostrin, and flotrane, main hormones used in the production of Class-specific pheromones and natural pheromones. 

• Ampheprotin Epzitriene - Morph - a type of pheromone suppressor; meant to be ingested every 9 hours. Does not need to be digested with food or drink. Do not use more than two per day. 
• Neustrin Benazebrate - Nether - another version of pheromone suppressor that lasts 4 hours. Can send system shock if used more than 3 times in 24 hours. Should be taken with food and water. 
• Neufranil Adapaxolol - Witch’s Mist (or Mist) - a type of pheromone suppressor ingested with water. Only use one a day. Can malfunction when experiencing high emotional levels. 
• Serophine - Patch - a knockoff pheromone suppressor; faux skin on scent glands of neck and small of wrist. Can cause rash or skin irritation if used incorrectly or too much. 

Other 

• Pediavac - N/A - can be used to help Littles into headspace if they naturally struggle or have an imbalance. Used as a multivitamin to be mixed with formula or juice. 
• Nutripen - N/A - used to help chemical imbalance for Littles suffering severe headspace neglect or natural imbalance (ONLY USED IN SEVERE CASES) 
• Nutrostryl - N/A - another version of nutripen. Can be used in less intense cases or in food as a supplement. 
• Fluotestryl - N/A - a daily nutrient supplement similar to Pediavac, mostly used for older Littles 
• Drospistrin - Droplet - a street drug knockoff version of Nutripen. Some dealers have used it to trick Littles into their headspace, making them think it was a suppressor 

Caregiver Specific 

* Baby Fever Syndrome = someone in the CG class experiences an imbalance in oxytocin (excess), novadrocin, and trulphine for a period of time (typically 7 months), and experiences a visceral desire to care for a Little, and may compulsively buy Little items (diapers, clothes, etc) in preparation for their future Little. May also be overprotective over non-CG peers. Natural reaction after initial classification; health problems occur after 10 months of this state. Can be seen in CG’s grieving a Little. 

• Oxycoriva - Oxy - given to CG’s experiencing Baby Fever Syndrome* 10+ months after classification; meant to inhibit oxytocin levels 
• Oxynarix - N/A - same as above
• Trulofoxin - N/A - same as above, for people who cannot take the above medications 

Other*

* feral behavior is caused by an excess of trulphine, and a severe hormonal imbalance within the endocrine system. 

• Aggrelin - N/A - used to help chemical imbalance of those in feral state. most common for phase 1 & 2 of feral state 
• Humunitor - N/A - a medication for those in p3 of feral 
• Propramicin Alduratant - Adulting - commonly prescribed for phase 4 feral

Other Info:

Villains and Vigilantes that are Little or Little-leaning Switches are a bit of a gray area. Dependent on their offenses, a Little Vigilante or Villain may not be legally or socially recognized as one. Rehabilitation programs exist to resocialize Little Villains and Vigilantes. 

Socially, Littles are often seen as their headspace age/subclass, even if they are physically and temporally an adult. Legally, it's a bit of a gray area and depends on the prefecture/region and their interarea politics.