A big part of story telling involves emotions. Love, hate, guilt, fear, elation... Here's a tip on writing a love scene with character-appropriate emotion.
The most important thing to remember about love scenes is that they must fit the temperament of your characters. This should, of course , be true of all your characters' actions, but with love scenes it's especially critical because is't so easy to slip into cliché. By the time you write that big romantic scene in your novel, you have read or seen on television and at the movies hundreds of love scenes. The twin temptations are slipping into unthinking repetition and wanting to do something completely new. If you simply repeat the usual romantic speeches and actions, your scene will be boring. There are, after all, only so many things lovers usually say or do when they declare love; how can you make them fresh? And if you strive too hard to do so, you may stretch the reader's credulity to the breaking point. The answer, again, is to use the conventional actions but with attention to your characters' individual personalities. They can still use the usual variations on the basic human formula ("I love you." "Will you marry me?"). They can do the usual things (embrace, kiss). But their other words, their gestures, the props in the scene, the setting, the emotions they feel in addition to simple desire present enormous potential for individualizing the universal.
Character-appropriate emotion combined with characters' mannerisms, history, and the era of the story can all add a special spark, a unique experience to the love scene.
Characters, Emotions & Viewpoint - Techniques and exercises for crafting dynamic characters and effective viewpoints by Nancy Kress.
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