[whsie]

Originally Posted by Okashira

No, this has been talked a lot before: Shiba Tatsuya uses -> 司波 and 達也 , of which none are a number kanji. erm.... Isn't that a spoiler that should be tagged?

About why they have a certain place, I think it was mentioned within the thread? I think that it was about importance and influence rather than something dumb like power levels.

You are partially correct, BUT...

Spoiler for spoiler:

Tatsuya's surname was purposely named to sound phonetically similar to the word "Four" in Japanese. He's part of the "Four" clan, yet he doesn't have actual surname of the "Four" (四夜) clan (literal translation is Four Nights). That said, cyberdemon is correct about the student president. The student council president literally has the word "Seven" in her name just as the other clan members of the numbered families have the actual number in their name. For example, the student council president in the actual literal translation in Chinese will read like Qi Cao （七草） or Seven Grasses. Jumonji's last name reads like Shi Wen Zi （十文字） or Ten Scholarly Words. As you see, the actual number is in the name and that's how people recognize if a person is from a numbered family.

Spoiler for Clans:

You'll reach this really soon if you're reading the manga, but the number families are the most influential and powerful clans in the story. There are the ten primary clans (one through ten) and a set of subsidiary clans that are also numbered (e.g. Thousand). The strongest and most influential clan is "Seven", which is also the clan the student council president is in (I believe she is the daughter of the head). The one clan that rivals the "Seven" clan is the "Four" clan. The "Four" clan is also the most mysterious and dangerous clan. Few know little about the "Four" clan. Most that do know are dead because "Four" symbolizes "Death" (like Tatsuya's last name, "death" and "four" are phonetically similar in Japanese/Chinese). The "Four" clan is known in the world for it's small, but elite group of magicians. None of the magicians are below Combat-level (e.g. Miyuki is combat-level) and they're nearly untouchable because they monopolize CAD and weapons manufacturing. Other clans dominate different sectors of society. For example, one (I think the Ten clan) dominates the military sector.

A lot of the top dogs in the first four volume are from the number families. Unofficially, Miyuki and Tatsuya are part of the "Four" clan. The student council president is part of the "Seven" clan. Jumonji is the next in line for the "Ten" clan. Mori is an exception. The Crimson Prince in volume 4/web 2 is the next in line for the "One" clan.

EDIT: Clarification on Numbers in the name for the first spoiler.