Have you had the chance to look at the link I posted in the last post? It has a lot of hints and tips for new authors. If you have any other questions, you can always ask one of us through pm. I do agree starting a story is tough though. Ideas just don't develop overnight, and oftentimes it takes brainstorming to formulate. What you need first is a general outline of how the plot progresses. What happens in the story on down the line? More importantly, what will the end result be? Have that in mind and work towards it.
Think about the kinds of characters you want. For your story idea, it seems like you have two primary characters: the submissive character is exactly how you describe him. Think about things he would say and how someone like him could end up in that kind of position. Also, what is your other character like? The only things you've really given us is appearances. Their personality needs developed as well. Is she shy, or does she take charge? Is she cheery or is she seductive? What about her motives for tying up the poor guy? Does the guy have something she wants, or is it just on a whim? Is she a mutant that seeks to destroy the world by somehow detonating the submissive that causes a massive cataclysm(just joking)?
Another is style. I've seen two primary styles used. One is the third person style. "Johnny says this. Johnny thinks about him. Johnny wants that. The object in the corner was picked up by her" are examples. If there are multiple plot lines, then this one is better. It's not as personal as the other style I'm about to describe, which is the first person stream of consciousness style. "I didn't know what was going on." She was the most beautiful girl I've seen. I shriveled as she pulled the item out of the box." These are examples of talking from the mind of the main character. It focuses on more of what the character is thinking rather than the general environment. The second option might be better for a two-character plot.
Some other formal things to think about is spacing. Dividing your story into several groups of sentences is much easier to read than chunky groups of paragraphs. Your readers will thank you for it.
Ha, yea this is way off topic, but oh well. I will quit here and if you have any other questions, don't hesitate to ask. Storytelling is like many other hobbies: practice and feedback make perfection..or close to it.

Oh, and don't forget to check out this link:
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