If you thought pizza crust stuffed with bacon or a burrito-quesadilla hybrid was risky fast food, then you are not ready to handle what Burger King is doing in Japan.

This is the Kuro Diamond. More appetizing, but still ... (Photo: Burger King)

Next week, the Wall Street Journal reports on its Japan Real Time blog, the fast-food chain will start selling two cheeseburgers with black buns, sauce and cheese. The Kuro Pearl and Kuro Diamond burgers will be available for a limited time beginning Sept. 19. Kuro means "black" in Japanese. The Pearl is a patty, cheese and sauce, while the deluxe Diamond version includes lettuce, tomato and onions.

This actually isn't the first time Burger King has sold a black-bun burger, according to Kotaku. But this one has black cheese, and for some reason, that is far, far more disturbing. Bamboo charcoal is used to make the bun and cheese black.

According to the WSJ blog, BK Japan brought back the black burger because it sold well in the previous run.