Basic information about tower
There are Guardians for each Floor (except the 43rd Floor) and they have control over the shinsu on their Floor.[1] Note: everyone in the Tower requires shinsu to breathe (including all Irregulars) as shinsu replaces oxygen and water (substances which constitute the atmosphere outside the Tower).
Without a Guardian, a Ruler can't rule.
There are Rulers for each Floor (excluding the First Floor and the 43rd Floor) and they rule over their Floors under the permission of the Guardians. The Rulers are all High Rankers.[1]
Other than the Ruler, it is likely the rest of the Staff (Test Directors, instructors, etc.) are found in the Inner Tower as they have to carry out or watch over the tests or perform other tasks on the Floor.
In the Tower, you need a contract with the Guardian to manipulate a certain amount of shinsu without a special item.[2][3]
The Tower is populated by creatures known as Shinheuh.
Residents of Tower have a large lifespan. In addition to that, if they learn how to manipulate shinsu their lifespan will immediately increase to the point it looks like their aging process has frozen.
Sometimes when people start to handle shinsu their growth stops before they become adults, then it's standard to treat them like kids regardless of age. The general theory in the Tower is that the growth of the body is proportional to the growth of mind. There are exceptions by the region of origin or families.[4]
However, there are also cases like a person contracting diseases or develops an allergic reaction to shinsu as they get older, and the cells start to function improperly due to it, which is quite similar to cancer. If someone dies of old age in the Tower, this is usually the case.
There are confirmed cases of Rankers obtaining immortality. For example Zahard and the 10 Great Family Heads were rewarded with immortality by the Guardian of 100th Floor for passing its test.
Age is only a number in the Tower so it isn't worth thinking about. People consider body age or species characteristics age something not important. And the superior-subordinate relationship according to age does not exist, as rank or status are considered over age.[4] For example Yuri, Khun and Androssi do not use honorifics for almost everyone because they are from the 10 Families, however Anak does use honorifics.
Regular- Regular, is an individual chosen by Headon and permitted by the Zahard Empire to climb the Tower.
Irregular- members who have not been chosen" or "Irregulars"), more commonly known as simply an Irregular, is someone who was not selected
Ranker- Ranker are those individuals who reached the 134 Floor and have been given a rank. This Rank is issued by the Ranking Administration Office and it is calculated after investigating and combining statistics such as a person's power, recognition and influence.
High ranker- if a Ranker's ranking is in the top 1% of total Rankers, he/she is considered a High Ranker There are about 1000 High Rankers in total. High Rankers are often described as gods among gods. Only those of a level equal to a High Ranker can become a Ruler.
Shinsu- Shinsu exists everywhere inside the Tower. Shinsu does not flow from the Outside, but is rather "created" and "produced" by the Tower itself. Shinsu can even exist in a vacuum.As of now, what Shinsu consists of or comes from is unknown
Zahard- Zahard is the famed "King of the Tower" and the most famous and greatest being residing inside; he is like a god to the inhabitants of the Tower. He is a High Ranker, currently retaining the 3rd spot in the ranking, and the overarching ruler of Zahard's Floors and founder of the Zahard Empire while still conquering the Tower.
FUG- FUG led by Grace Mirchea Luslec, is the most dangerous and secretive criminal syndicate in the Tower. Their official members wear the "Mark of the Slayer".