Mourabiteau Identification and Distinction Number

A mourabiteau identification and distinction number (French: numéro d'identification et de distinction mourabitean; Latin: numerus identificationis et distinctionis murabito) is a form of mourabiteau identification using a combination of letters and numbers.
== Details ==
Each digit of the number is associated with a feature of the mourb.
For example, Matt's MIDN is A30aM00TWC1. Deconstructed:
* A - his skin colour. He has the lightest skin colour registered by the Social Meteorologists' census board. There are 8 skin colours registered from A to H, decreasing in brightness.
* 30a - his usual hair style and colour. #30 is the designation of his specific haircut as depicted in the series and a is the colour as set forth by the census board, in this case black. There are 47 hair styles and 16 hair colours registered.
* M00 - his eye shape and colour. M is the designation of his specific eye shape and 00 is the colour as set forth by the census board, in this case black. There are 26 eye shapes and 12 eye colours registered.
* T - his nose shape. T means triangle, O means elliptical/oval, and R means rectangular.
* W - his mouth shape. S means small, W means wide, U means "UWU" and B means "bucktooth".
* C - how intense his blush is whenever it arises. C means "calm" or almost no blush at all, M means medium, and E means "embarrassed"; i.e., their blush is very noticeable, as if they're embarrassed.
* 1 - his biological gender. 1 means they're a cisgender male; 2 a cisgender female; 3 a transgender male; 4 a transgender female and all those who are queer and otherwise are 5.
There could only be exactly 337,858,560 unique mourbs before there is a conflict. Aside from the MIDN, there is also a villager number, to further enhance the distinction between mourbs of the same appearance.
For mourbs that drastically change their appearance after registering at least once, they need to also change their MIDN. However MIDN changes are relatively easy considering this fact, but will leave a history on whoever changes their look, probably for tracking in case of crimes by the mourb. It is automatically validated and updated whenever the mourb leaves the country and re-enters it, and in every parlor.
=== Mattheunoids ===
Mattheunoids (from Mattheus; Matthew or Matt) are mourbs that look almost exactly like Matt and as a result share almost the exact same MIDN as him with noticeable differences only being in the skin colour, blush and gender.
The reason for their similarity is either from coincidence or for fun. Similar to how MoistCr1tikal Charlie spawned a trend where there were a lot of people resembling and acting like him, mattheunoids do what they do because they like acting like Matt either to ridicule him or to be in support of him, since Matt is mentally different from most mourbs.