Notes:

It’s interesting to note that Ryuuko’s name has like 8 symbolic meanings to it.
First, her name in kanji, hiragana and romaji: 流子 = りゅうこ = Ryuuko
-The straightforward meaning is: 流れ子 = Wandering child, stray child
-The sad hidden meaning is: 流された子 = Child that was washed away, abandoned child
-The cool meaning is: 流星子 = りゅうせいこ = Meteor child
-The thematically relevant meaning is: 流行 = Ryuukou = Fashion
-The self-evident meaning is: りゅうこ = Ryuuko = Hero
-The clever meaning is: りゅうこ = Ryuuko = Two big rivals
-The homage meaning is that Ryuuko’s name is a direct reference to the protagonist of Otokogumi; as you may remember from the original interview, Kill la Kill started as a big homage to Otokogumi. Otokogumi’s hero was called 流, Nagare. They added the 子 so it would become a girl name: 流子 = Nagare-ko = Girl Nagare; the reason they decided on the Ryuuko reading of the kanji makes it even cooler as a homage and you will see why on the eight meaning.
-The love interest of Otokogumi’s Nagare was called 涼子 = りょうこ = Ryouko; Ryuuko’s name is basically the combination of Ryouko’s and Nagare’s names, as if she was their successor of sorts.
Also, in the Febri interview Nakashima himself said to pay attention to the “流された子” meaning and it makes perfect sense now; they probably hinted to it in episode 12 when Isshin said that he has no sense for naming and just calls things what they are. When he found Ryuuko, Isshin literally named her “abandoned child” because that’s exactly what she is.
Speaking of hidden meanings, this month’s NewType spread (pictured) has a whole new sense to it now… specially considering the big red text reads “THE GENE OF REBELLION”.
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