>>713388015
Most guys and girls are into stuff about themselves or characters they'd like to be.
However some segment of the audience are into things about the opposite sex, especially those with a variety of designs and interactions, when they essentially serve as a figurative peep into the lives of those they're curious about but are usually outside the social circle of.
Ouran High School Host Club comments on how this party platter approach signals, intentionally or otherwise, something to viewers interested in the spice of a sex.
A consistent, developing cast with older guys, younger guys, tall, short, smart, dumb, violent, soft, friendly, antagonistic, etc is more likely to net interest.
In Harry Potter you have the meek but wily Harry, the pauper best bud Ron and his mischievous older twin brothers, rich bully Draco, gloomy Snape, Papa Bear Hagrid. Slim, but still something, and since readers observe them grow as individuals and pairs there's more payoff to remaining invested.
Hermione, Ron's sister and that one Asian chick exist but usually off to the side.
But there are technicalities to this sort of thing, an all male cast that's too similar or in a genre not prone to dynamics that are relatable or pleasant, like most War stories, probably won't draw as much as a school setting with gradations of the specimen of study and opportunities to foster an atmosphere for rivals to "frenemies" or two guys fighting for "dominance" or freshman and senior S&M "student and mentor" and so on.
