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Mary Hogan's "The Serious Kiss," may have more than one theme, but what seems most prevalent to me is the desire of Libby and Nadine to find that which they believe will make them most happy.
Libby is unhappy with her family; she is afraid to eat for fear of gaining weight. She is embarrassed by her mother. "Life" is not living up to her expectations. She has a best friend, and hopes that despite everything else in the world, Nadine and she will continue to be friends.
However, what both fourteen-year-old girls agree upon is that their most fervent wish is to find love.
Leaning back on the rubber pillow of my raft, I tried to imagine it. The 'it' we were both talking about, of course, was the big it, the it supreme: Love.
They both have the same definition of love:
...then we both said the exact same thing at the exact same time: 'Love is a serious kiss.'
It cannot be messy or half-hearted, but must encompass all that is wonderful in the world. Their descriptions of a "serious kiss" are sweet and humorous. It is the stuff "dreams are made of." And their goal is to experience this event before they turn fifteen.
So in answer to your question, I believe the overall theme here is the experience common to most people: it is the search for love in the world. And by finding this kind of love, I believe that Libby, at least, hopes to find a way to love the world back and love herself as well.