That's what you get for daring to read a writer's raw notes.

In finished form (and undoubtedly in the movie itself, were it ever made) the scenes in question would be implied through allusion rather than shown fully on screen.

Allow me to quote an eminent scholar of Victorian literature:

Many Victorian fiction authors sometimes wrote deliberately incorrect and seemingly absurd passages into their books, especially in moments touching on sexuality. This was done so that only people who were mature enough to understand what was in all likelihood really happening would interpret the text correctly.

This practice was not at all uncommon among Victorian writers, even those working in non-fiction fields. For example, popular English-language medical textbooks of the day switched to Latin to describe ailments of the genitals, or other material that might be considered “prurient.”

Of course, this style of fiction writing expects that the reader be prepared to look for such code phrases. Yet, equally, it asks that its readers exercise their own imaginations.

This philosophy is one which GL seems to have followed himself in writing the various scripts of the original SW film.

Incidentally, the symbolism of the scene in question is an allusion of sorts referring to the Ancient Greek notion of the four bodily humors: black bile, yellow bile, blood, and phlegm.