Minazuki Karen is a half human, half Coco and Nuts's species.One of Karen's parents (for convenience, let's say her father) is originally from the Kingdom of Palmier, one of the rare residents who can take human forms like Coco and Nuts. He was helping Coco search for the Dream Collet, but he got sidetracked when he met and fell in love with a human woman. They married and had a daughter, Karen. Mr. Minazuki wanted Karen to have a normal life, which she wouldn't if she discovered her father's true nature. So, before she was old enough to remember his mascot animal form, he and Mrs. Minazuki went permanently "on tour," intentionally overcrowding their schedule so Karen would only see them one day a year (during which he could hide his secret easily), when normally they should be able to leave enough days free to make time for trips home to their daughter. Because of her biological connection to Palmier, Karen displays a few odd traits. Like Coco (as Kouji) did early on, she successfully calls forth a butterfly before she is able to become Cure Aqua. Later, she produces a sword from the Aqua Ribbon, a technique which no other Cures have duplicated. Karen has no physical transformation, but Masukomi-ka has noted that she undergoes a drastic personality shift, similar to Coco's, when among friends. And like Coco and Nuts in their human forms, Karen appears to draw female admirers like moths to a pitcher plant. This is also why Nozomi (who has a natural tendency to find things from Palmier) was so certain Karen was the right choice for the Pretty Cure of Intelligence. Sub-theories:
Karen is related to CocoPerhaps she's his cousin or niece. Thus, her similarities to Coco in particular.
Cure Aqua is a Legacy CharacterMrs. Minazuki assisted Mr. Minazuki as the previous Cure Aqua in a situation paralleling Coco and Nozomi. Uncanny Family Resemblance will last forever.