My favorite genre is sci-fi. Apparently, I’m in the minority. In Germany, sci-fi accounts for only about 5% of the book market—and that’s only because it’s lumped together with fantasy. If you remove Harry Potter, The Hunger Games, The Lord of the Rings, and Game of Thrones, the genre probably makes up closer to just 2%.

I also enjoy reading comics, which officially represent around 8% of the market. However, in Germany, comics are grouped together with cartoons, humor, and satire, so the actual share of graphic novels is significantly lower.

Every now and then, I throw in a James Bond adventure, continue my Reacher journey, or pick up another crime or spy novel. This genre is firmly in the mainstream. Combined with horror and thrillers, the crime genre accounts for nearly 25% of book sales.

But there’s one genre that towers over all the others: Romance.

I’ve seen data from the U.S. suggesting that nearly half of all book sales fall into this category. In Germany, the numbers are a bit lower, but romance and love stories still top the charts. I even read once that romance novels with explicit content—basically erotica—sell as much as thrillers, fantasy, and sci-fi combined.

Whew. Thinking about that, I realized: I’ve never read a book anywhere near that genre. And I doubt I ever will. If I don’t enjoy reading something, I certainly won’t enjoy writing it. So don’t expect any romance novels from me anytime soon.

Thinking about my family and friends, I can’t name a single person who reads romance either. So I asked myself: Who’s buying all these books?

Then it hit me: it’s the women.

Women make up 65% of all book buyers.

Is it any wonder that publishers today mostly sign female authors? Does it surprise why Amazon promotes such books in every search query? Or that books targeted at women are the first thing you see when you walk into a bookstore?

So, if you’re in it for the money, write romance—and aim it at women.

If you’re in it for the fun, stick with robots and spy detectives. And maybe—just maybe—you’ll attract a few of the last men standing who still read more than 140 characters at a time. But even if you don’t, the joy of sending your protagonist on a journey across time and space will always beat writing yet another version of Christian Grey falling for your average barista named Bella from the corner coffee shop.

At least, if you’re a man.