Another way to approach it is to have him read one or a few stories where the Master/Dom deals with the sub/slave in the ways that you need. Emphasize to him how much you love the story, how hot it is, or how much you identify with the sub in the story. While he might at first think of it simply as entertaining (hopefully) if you are adamant about your passion for the scenes, it might have an effect. Sometimes hints like that help get the point across if you can't find the right words.

That might be a more subtle way of directing him to this site, as well.