Lettuce is my favorite one of the girls. Interestingly however they made her much less shy and clumsy than she was in the original manga. Not that that was a problem I've just wondered why they did that.
It's supposed to be a sort of pun/ironic thing/bleh about how they all work in a cafe. There was something about Retasu, Minto, Purin, and Berri all actually have different meanings, but I don't remember what it was exactly. Also, don't forget Ringo~ Apple .w. Ichigo and Zakuro are normal actually, Ichigo is used in a lot of anime XD Zakuro just sounds cool~
@emeliakanson91 Castanets are indeed from Spain. She is actually a dolphin, but her Mew Aqua form looks mermaid-like. Although, officially, it is simply her with a dolphin tail.