The movie Father Figure 2 has the older/younger. Baccus (sp?) has a lot of movies with the older, more muscular guy getting serviced by a younger guy. If you want that, check out stuffy under any title with the words Dad and Son in them. It implies incest, but it never is real. I've also heard of the movie Squirt, but I think that's in reverse of what you want, but I'm not sure.

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