Alter Aeon Rules of Conduct
Rule 15.6 - Informational - storage characters
The technical rule is that players are only allowed one storage character per
main character. This is somewhat difficult to detect, however this rule is
occasionally enforced.
Generally, if you're a complete storage hog, the gods will request that you
condense your storage and reduce the number of storage characters to a
smaller number.
Honestly though, if you have that much storage, there's probably something
wrong with you.