I suggest that the distinction between a psyche being "ego-oriented" or "affect-oriented" also applies to narratives.
In that essay I illustrated this difference in orientation by comparing two famous Rider Haggard novels, but both novels contain just one focal character who is either the center of all "ego-oriented" or "affect-oriented" narrative attention.
Prior to that essay, I had discussed in some detail the concept of the "ensemble," here and here.
ENSEMBLES ASSEMBLE established simply that it is possible for a work to possess two or more "focal presences," who may work as a team (the two alleged vampires in 1935's MARK OF THE VAMPIRE, various superhero groups) or may be utterly opposed (1934's THE BLACK CAT, 1968's WAR OF THE GARGANTUAS). The latter is an important point in that the concept of "mortal enemies" pervades most if not all literary genres in one way or another. Usually either a "hero" or a "villain" alone is the focal presence, just as one sees with the examples from Haggard: the "heroic" Allen Quatermain and the "villainous" She-Who-Must-Be-Obeyed.
It's usually easy to identify when a team of heroes- or even demiheroes-- constitutes the narrative's focal presence: they're often the featured characters with whom the reader identifies in an "ego-oriented" manner. Villains and monsters, who are dominantly types set against the welfare of a given community, are usually treated like "She," as fascinating affects, but they don't tend to form "teams" quite as often.
In CREATOR AND CREATED ENSEMBLED HE THEM I set forth my meditations regarding several famous interdependent "creator-and-created" characters from the horror genre: Doctor Jekyll and Mister Hyde, Frankenstein and his monster, and Doctor Moreau and his beast-men. Though all are "affect-oriented" types, I determined that only Frankenstein and his monster shared "ensemble status" in their original appearance. Stevenson's original Mister Hyde was a "created" being who did not share ensemble status with his creator Jekyll, while to the contrary monster-maker Doctor Moreau was the sole focal presence of Wells' novel, with the beast-men rating as no more than "excresences." However, I also pointed out that any of these narrative arrangements could change in an adaptation of the same characters, and provided the example of the Universal Frankenstein series, which tended to emphasize the Monster far more than the creator. Other critics have pointed out that the Hammer Frankenstein series pursued the opposite strategy.
Now, as to my method of making those determinations, I must admit that I deem this a "pure deductive" judgment that cannot be proved analytically. This sort of judgment is not notably different from most judgments about literary structure and/or merit. The closest I can come to concretizing this abstract process is to say that the thing that makes one or more characters occupy the imaginative center of a story may be best compared to the crossing of a threshold, a metaphor I used earlier here.
During the last year, in my reviews on my movie-review blog, I've been pursuing with some diligence the nature of that subgenre of horror/SF called "the giant monster film." Almost without exception, any time there is but one giant monster in the narrative, it will be affect-oriented, as I wrote with regard to 1933's KING KONG. The same dynamic applies to Kong's most successful cinematic imitator, GODZILLA.
However, the original Godzilla series shows far more variability than either of the aforementioned Frankenstein series-concepts. In the first sequel to the original GODZILLA, the script instituted a practice derived from the 1933 KING KONG but different in its permutations. Just as King Kong battled assorted giant monsters who did not share "ensemble status" with the titular monster, in GODZILLA RAIDS AGAIN the Big G fights a second monster, one Anguirus. I doubt that anyone would question that Anguirus plays a secondary role in this role, that he does not enjoy ensemble status.
However, the very next Godzilla film creates a team of "mortal enemies" who do share that status, and I remarked on this in my KING KONG review:
Some "affect-oriented" works even offer two focal presences for the price of one, as in Japan's 1962 KING KONG VS. GODZILLA.
The same was true of the next Godzilla entry, MOTHRA VS. GODZILLA, even though structurally speaking the film seems more of a sequel to the first MOTHRA.
The next two films in the series presented the first "monster teams" in the series, with the narrative interest in the ensemble consisting of Godzilla, Rodan, and (in only one of the two films) Mothra, as they battle against common enemy Ghidrah. Afterward the original "Showa" series varied between using Godzilla as a "solo star" opposed to some other monster or monsters, or teaming him up with either a new character or with an old standby. Even Anguirus, who was a simple monster-antagonist to Godzilla and was killed off in his first outing, was revived to serve as part of an "all-monster squad" in 1968's DESTROY ALL MONSTERS and even becomes part of a two-monster team with his old enemy the Big G in 1972's GODZILLA VS. GIGAN.
In contrast to this practice by Japan's Toho Studio, most American studios, when they were doing giant-monster films at all, confined themselves always to the pattern of having just one giant affect-oriented creature who had to be destroyed by story's end. Only the fantasy-films of Ray Harryhausen and a few imitators attempt to create "monster mythologies," though none of these were employed for more than one. Arguably the culture of the Japanese, given their polytheistic heritage, may have provided more fertile ground for such mythologies than any comparable attempt from the United States or the handful of European countries that contributed works to this subgenre.