The reason that Aokoji is probably typed is that I and O are right next to each other on the keyboard, and your finger is probably already over the O from "Ao", and it isn't moved over far enough to hit the first I in "Kiji".
In other words, a typo.
Isn't it then also Aka Inu (Red Dog) and Ki zaru (Yellow Monkey)?
I think Oda melded the words together to make the names. But if it really is "Ao Koji", then its definitely also "Aka Inu" and "Ki Zaru".
One thing I would like to mention here.
The names of the three admirals are
not "Aokiji", "Kizaru", or "Akainu". Their names are 青雉, 黄猿, and 赤犬.
If you are one of the people that doesn't have a clue about Japanese (which accounts for most manga fans), those little chicken scratch symbols mean nothing to you (and indeed, the only one I can recognize without assistance is 犬).
Rather than use the meaning of the names (Blue Pheasant, Yellow Monkey, Red Dog), most translators use
romaji.
Romaji is
not related to Japanese in any way. It's only use is to approximate the pronunciation of Japanese words using the Latin alphabet, and it does this with decent (though far from perfect) success.
When large amounts of Kanji are smushed together to make a huge compound word, the translator to romaji often adds spaces in between certain spots to break it up into easier to understand and pronounce chunks.
Take, for example, 黒縄天譴明王. It's one big compound name, so without space breaks it would be romanized as
Kokujoutengenmyouou. Bleach fans might not even realize at first glance that I just named Komamura's Bankai. Unless you're German, most people have a really hard time pronouncing and understanding a word that big, so spaces are added to break it up and make it
Kokujou Tengen Myou'ou, which is much easier on the eyes to read.
So, when asking whether "Aka Inu" or "Akainu" is correct, they both technically are.
Japanese doesn't have any spaces at all. Ever. The spaces are added in the translation to help understand and pronounce the word better.
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