Story of the anime is about Kurashita Tsukumi, a huge fan of jellyfish, living in an apartment complex together with other girls from the ugly/dorky category, and a no-men-allowed rule.
One day Tsukumi meets a beautiful person, who helps her out saving a jellyfish, and in return she allows said person to spend the night. Only by morning does she realize that the person is actually a guy, who likes to dress as a girl.
The moment I heard the title Kuragehime (jellyfish princess) the first that came to my mind was this picture:
Then I saw the opening... which I can only recommend everyone to watch, cause it's really funny!
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