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全開学園, aka "Full Open Academy".
A very old series by artist Duke from the mid 90s. A play on "Zenra Gakuen" (Zenra, of course, being "Stark Naked"), Zenkai Gakuen is a combination of the old "Emperor's New Clothes" fable and, well, high school.
In Zenkai Gakuen, the public school has standardized using a specific, somewhat mundane uniform -- except for the material that it is made out of. This strange cloth is completely invisible to anyone with an IQ of less than 65536 -- all they see are the collar of the shirt, the tie, and the footwear.
Underwear and casual wear are also provided by the school.
Of course, no one ever admits they can't see the uniform. That would be tantamount to admitting the aren't very smart.
There is a similar uniform for the elementary school, as well as a boy's uniform -- the boys are mercifully not drawn by Duke, however.
And, just like the original fable, the 8 year old little sister of the main female lead is fully aware that the uniform doesn't actually exist, and that her sister and herself are all walking around completely starkers.
However, A public prosecutor went after the school, only to discover to her dismay that the uniform apparently DOES appear on film.
Some fairly well known artists including AVX have drawn fanart of the series over the years, unfortunately most of it has been lost over several website closures.
Characters
- Hazuki Chigusa (Brown haired girl)
- Hazuki Chisato (Chigusa's younger sister)
- Copperfield Rumiko (Blonde girl)
- Copperfield Kumiko (Rumiko's sister)
- Kashiwada Yayoi (Meganekko)