Brent Lang Executive Editor of Film and Media“Mortal Kombat” and “Demon Slayer: Kimetsu no Yaiba” are locked in a fierce battle for box office dominance.“Demon Slayer” has a slight edge at this point, earning $9.5 million from 1,598 locations on Friday. The Funimation and Aniplex of America release is based on an anime series and enters the U.S.