Demon Ranking System (鬼の序列 Omi No Jorestsu) is a system used to determine a demon's strength among all demons in the Demon World, or mainly among their peers inside the Babylus Academy. They can do this by proving themselves in tests designed to assess their strength, perform feats or gain accomplishments.
Since the main series acknowledges and focuses the Demon Ranking System moreover inside the Babyls Academy, this article discusses the latter more than its effect in the whole Netherworld.
The Demon Ranking System classifies a demon's status in the demon world. Presumably, they start their ranking when they first go to a demon school, increase and/or decrease it through school activities, and even after they graduate, they keep their rank and may be able to increase it quite further.
Usage in School
All starting students (freshman, tranferees and exchange students) are unranked, and has specific non-ranking state during their first days of school. In given time, students, after classified through class, will be given a test to be so that the students will be analysed for their ranking, such as the demon-familiar summoning exam and racing exam. After, they are then classified by a ranking owl. The ranking owl has a pouch on its stomach that contents the ranking badges, of which each students are required to put their hands in and grab their base respective ranks. Most of the time, first years are categorized into Aleph (1) and Bet (2) rankings.
Notably, a most common stereotype inside the school is being conceded based on your ranking. If one's rank is different than the majority, they would be considered popular. The higher it is, the greater you are acknowledged. Though there are few exceptions such as even though Iruma was unranked, he got considerable amount of attention due to some events and circumstances, as well as being connected and related to the head of the school himself.
In addition, the availability and the quality of the food that can be ordered in the school's cafeteria depends on their rank as well. For instance, there are only narrow details to order for low-ranking demons, but on the other hand, there's an extensive and huge variations to pick from for the high-ranking ones. Besides to the fact that all of the food are free for all students, anyone can access the lowest-tier of food as well which is mostly for the new and unranked demons, though the quality of the food is much worst than the Aleph-ranked dishes. 
Rise or Fall Ranking
A rise in rank can be granted to the students of Barbirus by the principal, Lord Sullivan, or any authorized Babylus Demon School Staff. For the freshmen, there are five ways to increase their ranks. Namely, they are the (1) Cannonball Execution, the (2) Division Party, the (3) First Term Final Exams, the (4) Harvest Festival and the (5) Music Festival. Each has different contributing factor and procedures on how they increase student ranks, such as during the Division party that one must be part of a Divison group. However, it is possible that the ranking of a demon can be reduced when they put the school in grave danger, or when a student scores significantly lower than the passing grade during Term Exams.
The following table lists the ranking from lowest (1) to highest (10) and their terms.
Lists of demons (and Iruma) that were shown of their badges based on their current rankings.
- The rating system is based off Gematria, a numerological system by which Hebrew letters correspond to numbers.
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