While the harem genre may seem like a strange and foreign concept that could only exist offshore, the west does have harem stories. We just don’t label them harems. A classic example is the comic character Archie, a “typical teenager” who’s 50 year history has centered around a love triangle between a childhood friend and rich girl. Later on Cheryl Blossom and Valerie Brown were added, making it officially a harem. Or what about Peter Parker, the amazing Spider-Man and certified “every man” hero, who’s in love with Gwen Stacy, Mary Jane, Black Cat, Betty Brant, etc. Then there’s James Bond, who has a different love interest every movie. It’s not only men. Bella Swan had to choose between a sexy vampire and hunky werewolf. Katniss was drawn to both Peta and childhood friend Gale. Western Harems do exists, because having multiple love interest is not only a way to boost sales and draw in audiences, it’s also a easy change to the plot.
But could an actual harem-like show exist in the west? No. Of course not. It’s too obviously sexist. You could not have a 13 episode sitcom were the actresses all threw themselves at the main character. Even Three’s Company in the 1970’s had the protagonist pretend he was gay. A reverse harem could probably work today (i.e. The New Girl).